diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
index 9db56f8b0c..4109ffeed7 100644
--- a/.github/workflows/tests.yaml
+++ b/.github/workflows/tests.yaml
@@ -16,7 +16,7 @@ concurrency:
 env:
   SHOWCASE_VERSION: 0.35.0
   PROTOC_VERSION: 3.20.2
-  OLDEST_PYTHON: 3.7
+  OLDEST_PYTHON: 3.9
   LATEST_STABLE_PYTHON: 3.14
   # TODO(https://github.com/googleapis/gapic-generator-python/issues/2450):
   # Switch this to Python 3.15 alpha1 pre-release
@@ -25,7 +25,7 @@ env:
   # TODO(https://github.com/googleapis/gapic-generator-python/issues/2450):
   # Add Python 3.15 alpha1 pre-release
   # https://peps.python.org/pep-0790/
-  ALL_PYTHON: "['3.7', '3.8', '3.9', '3.10', '3.11', '3.12', '3.13', '3.14']"
+  ALL_PYTHON: "['3.9', '3.10', '3.11', '3.12', '3.13', '3.14']"
 
 permissions:
   contents: read
@@ -93,9 +93,6 @@ jobs:
         # Run mypy on all of the supported python versions listed in setup.py
         # https://github.com/python/mypy/blob/master/setup.py
         python: ${{ fromJSON(needs.all_python_setup.outputs.all_python) }}
-        exclude:
-          # Remove once https://github.com/googleapis/gapic-generator-python/issues/2303 is fixed
-          - python: '3.7'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -119,9 +116,7 @@ jobs:
         target: [showcase, showcase_w_rest_async]
         logging_scope: ["", "google"]
 
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2303): use `ubuntu-latest` once this bug is fixed.
-    # Use ubuntu-22.04 until Python 3.7 is removed from the test matrix
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
       - name: Set up Python "${{ matrix.python }}"
@@ -212,9 +207,7 @@ jobs:
         variant: ['', _alternative_templates, _mixins, _alternative_templates_mixins, _w_rest_async]
         logging_scope: ["", "google"]
     
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2303): use `ubuntu-latest` once this bug is fixed.
-    # Use ubuntu-22.04 until Python 3.7 is removed from the test matrix
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
       - name: Set up Python "${{ matrix.python }}"
@@ -318,9 +311,7 @@ jobs:
     strategy:
       matrix:
         python: ${{ fromJSON(needs.all_python_setup.outputs.all_python) }}
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2303): use `ubuntu-latest` once this bug is fixed.
-    # Use ubuntu-22.04 until Python 3.7 is removed from the test matrix
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
       - name: Set up Python ${{ matrix.python }}
@@ -344,9 +335,7 @@ jobs:
       matrix:
         python: ${{ fromJSON(needs.all_python_setup.outputs.all_python) }}
         variant: ['', _alternative_templates]
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2303): use `ubuntu-latest` once this bug is fixed.
-    # Use ubuntu-22.04 until Python 3.7 is removed from the test matrix
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
       - name: Set up Python ${{ matrix.python }}
diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index 3df5a264d6..e120e905ab 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -18,7 +18,7 @@
 
 Execute unit tests by running one of the sessions prefixed with `unit-`.
 
--   Example: `nox -s unit-3.8`
+-   Example: `nox -s unit-3.13`
 -   See all Nox sessions with `nox -l`.
 
 ## Formatting
diff --git a/README.rst b/README.rst
index 5b38c1d7fb..08079f7f3a 100644
--- a/README.rst
+++ b/README.rst
@@ -5,7 +5,7 @@ API Client Generator for Python
 
 |release level| |pypi| |versions|
 
-    A generator for protocol buffer described APIs for and in Python 3.
+    A client library generator for APIs described through protocol buffers.
 
 This is a generator for API client libraries for APIs
 specified by `protocol buffers`_, such as those inside Google.
diff --git a/gapic/ads-templates/noxfile.py.j2 b/gapic/ads-templates/noxfile.py.j2
index 48646feb5e..c46e8a7d67 100644
--- a/gapic/ads-templates/noxfile.py.j2
+++ b/gapic/ads-templates/noxfile.py.j2
@@ -11,8 +11,6 @@ import nox  # type: ignore
 # Add tests for Python 3.15 alpha1
 # https://peps.python.org/pep-0790/
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/gapic/ads-templates/setup.py.j2 b/gapic/ads-templates/setup.py.j2
index 0824bc697c..79d2e0b3fa 100644
--- a/gapic/ads-templates/setup.py.j2
+++ b/gapic/ads-templates/setup.py.j2
@@ -34,6 +34,7 @@ dependencies = [
     "googleapis-common-protos >= 1.53.0",
     "grpcio >= 1.10.0",
     "proto-plus >= 1.22.3, <2.0.0",
+    "protobuf >= 4.25.8, <7.0.0",
     {% if api.requires_package(('google', 'iam', 'v1')) %}
     "grpc-google-iam-v1",
     {% endif %}
@@ -63,8 +64,6 @@ setuptools.setup(
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -76,7 +75,7 @@ setuptools.setup(
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     include_package_data=True,
     zip_safe=False,
diff --git a/gapic/templates/noxfile.py.j2 b/gapic/templates/noxfile.py.j2
index e11bf34bcf..a62637f5ad 100644
--- a/gapic/templates/noxfile.py.j2
+++ b/gapic/templates/noxfile.py.j2
@@ -33,8 +33,6 @@ if os.path.isdir("samples"):
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
@@ -287,7 +285,7 @@ def unit(session, protobuf_implementation):
 
 
 def install_systemtest_dependencies(session, *constraints):
-    session.install("--pre", "grpcio")
+    session.install("--pre", "grpcio<=1.62.2")
 
     session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES, *constraints)
 
@@ -506,7 +504,7 @@ def prerelease_deps(session, protobuf_implementation):
         "google-api-core",
         "google-auth",
         "grpc-google-iam-v1",
-        "grpcio",
+        "grpcio<=1.62.2",
         "grpcio-status",
         "protobuf",
         "proto-plus",
diff --git a/gapic/templates/setup.py.j2 b/gapic/templates/setup.py.j2
index 6573b942db..bff08c5006 100644
--- a/gapic/templates/setup.py.j2
+++ b/gapic/templates/setup.py.j2
@@ -33,7 +33,7 @@ else:
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -42,7 +42,7 @@ dependencies = [
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
     {# Explicitly exclude protobuf versions mentioned in https://cloud.google.com/support/bulletins#GCP-2022-019 #}
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
     {% for package_tuple, package_info in pypi_packages.items() %}
     {# Quick check to make sure `package_info.package_name` is not the package being generated so we don't circularly include this package in its own constraints file. #}
     {% if api.naming.warehouse_package_name != package_info.package_name %}
@@ -89,8 +89,6 @@ setuptools.setup(
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -102,7 +100,7 @@ setuptools.setup(
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/gapic/templates/testing/constraints-3.7.txt.j2 b/gapic/templates/testing/constraints-3.7.txt.j2
deleted file mode 100644
index d6d5cd5dd3..0000000000
--- a/gapic/templates/testing/constraints-3.7.txt.j2
+++ /dev/null
@@ -1,21 +0,0 @@
-{% from '_pypi_packages.j2' import pypi_packages %}
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
-{% for package_tuple, package_info in pypi_packages.items() %}
-{# Quick check to make sure `package_info.package_name` is not the package being generated so we don't circularly include this package in its own constraints file. #}
-{% if api.naming.warehouse_package_name != package_info.package_name %}
-{% if api.requires_package(package_tuple) %}
-{{ package_info.package_name }}=={{ package_info.lower_bound }}
-{% endif %}
-{% endif %}
-{% endfor %}
diff --git a/gapic/templates/testing/constraints-3.8.txt.j2 b/gapic/templates/testing/constraints-3.8.txt.j2
deleted file mode 100644
index e0f6dc7590..0000000000
--- a/gapic/templates/testing/constraints-3.8.txt.j2
+++ /dev/null
@@ -1,4 +0,0 @@
-# -*- coding: utf-8 -*-
-{% block constraints %}
-{% include "testing/_default_constraints.j2" %}
-{% endblock %}
\ No newline at end of file
diff --git a/gapic/templates/testing/constraints-3.9.txt.j2 b/gapic/templates/testing/constraints-3.9.txt.j2
index e0f6dc7590..1c6ec61fd8 100644
--- a/gapic/templates/testing/constraints-3.9.txt.j2
+++ b/gapic/templates/testing/constraints-3.9.txt.j2
@@ -1,4 +1,22 @@
 # -*- coding: utf-8 -*-
-{% block constraints %}
-{% include "testing/_default_constraints.j2" %}
-{% endblock %}
\ No newline at end of file
+{% from '_pypi_packages.j2' import pypi_packages %}
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
+{% for package_tuple, package_info in pypi_packages.items() %}
+{# Quick check to make sure `package_info.package_name` is not the package being generated so we don't circularly include this package in its own constraints file. #}
+{% if api.naming.warehouse_package_name != package_info.package_name %}
+{% if api.requires_package(package_tuple) %}
+{{ package_info.package_name }}=={{ package_info.lower_bound }}
+{% endif %}
+{% endif %}
+{% endfor %}
diff --git a/noxfile.py b/noxfile.py
index e99bfad597..9ec613d322 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -37,8 +37,6 @@
 BLACK_EXCLUDES = "|".join([".*golden.*", ".*pb2.py"])
 
 ALL_PYTHON = (
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
@@ -170,17 +168,13 @@ def fragment(session, use_ads_templates=False):
         "pytest",
         "pytest-cov",
         "pytest-xdist",
-        "asyncmock; python_version < '3.8'",
         "pytest-asyncio",
         "grpcio-tools",
     )
     session.install("-e", ".")
 
-    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2473):
-    # Warnings emitted from google-api-core starting in 2.28
-    # appear to cause issues when running protoc.
     # The specific failure is `Plugin output is unparseable`
-    if session.python in ("3.7", "3.8", "3.9", "3.10"):
+    if session.python in ("3.9", "3.10"):
         session.install("google-api-core<2.28")
 
     frag_files = (
@@ -250,7 +244,7 @@ def showcase_library(
     # Warnings emitted from google-api-core starting in 2.28
     # appear to cause issues when running protoc.
     # The specific failure is `Plugin output is unparseable`
-    if session.python in ("3.7", "3.8", "3.9", "3.10"):
+    if session.python in ("3.9", "3.10"):
         session.install("google-api-core<2.28")
 
     # Install a client library for Showcase.
@@ -357,40 +351,20 @@ def showcase_library(
                 f"{tmp_dir}/testing/constraints-{session.python}.txt"
             )
             # Install the library with a constraints file.
-            if session.python == "3.7":
-                session.install("-e", tmp_dir, "-r", constraints_path)
-                if rest_async_io_enabled:
-                    # NOTE: We re-install `google-api-core` and `google-auth` to override the respective
-                    # versions for each specified in constraints-3.7.txt. This is needed because async REST
-                    # is not supported with the minimum version of `google-api-core` and `google-auth`.
-                    # TODO(https://github.com/googleapis/gapic-generator-python/issues/2211): Remove hardcoded dependencies
-                    # from here and add a new constraints file for testing the minimum supported versions for async REST feature.
-                    session.install(
-                        "--no-cache-dir",
-                        "--force-reinstall",
-                        "google-api-core[grpc, async_rest]==2.21.0",
-                    )
-                    # session.install('--no-cache-dir', '--force-reinstall', "google-api-core==2.20.0")
-                    session.install(
-                        "--no-cache-dir",
-                        "--force-reinstall",
-                        "google-auth[aiohttp]==2.35.0",
-                    )
-            else:
-                session.install(
-                    "-e",
-                    tmp_dir + ("[async_rest]" if rest_async_io_enabled else ""),
-                    "-r",
-                    constraints_path,
-                )
-                # Exclude `google-auth==2.40.0` which contains a regression
-                # https://github.com/googleapis/gapic-generator-python/issues/2385
-                session.install(
-                    "--no-cache-dir",
-                    "--force-reinstall",
-                    "--upgrade",
-                    "google-auth[aiohttp]!=2.40.0",
-                )
+            session.install(
+                "-e",
+                tmp_dir + ("[async_rest]" if rest_async_io_enabled else ""),
+                "-r",
+                constraints_path,
+            )
+            # Exclude `google-auth==2.40.0` which contains a regression
+            # https://github.com/googleapis/gapic-generator-python/issues/2385
+            session.install(
+                "--no-cache-dir",
+                "--force-reinstall",
+                "--upgrade",
+                "google-auth[aiohttp]!=2.40.0",
+            )
         else:
             # The ads templates do not have constraints files.
             # See https://github.com/googleapis/gapic-generator-python/issues/1788
@@ -497,41 +471,23 @@ def run_showcase_unit_tests(session, fail_under=100, rest_async_io_enabled=False
         "pytest",
         "pytest-cov",
         "pytest-xdist",
-        "asyncmock; python_version < '3.8'",
         "pytest-asyncio",
     )
     # Run the tests.
-    # NOTE: async rest is not supported against the minimum supported version of google-api-core.
-    # Therefore, we ignore the coverage requirement in this case.
-    if session.python == "3.7" and rest_async_io_enabled:
-        session.run(
-            "py.test",
-            *(
-                session.posargs
-                or [
-                    "-n=auto",
-                    "--quiet",
-                    "--cov=google",
-                    "--cov-append",
-                    path.join("tests", "unit"),
-                ]
-            ),
-        )
-    else:
-        session.run(
-            "py.test",
-            *(
-                session.posargs
-                or [
-                    "-n=auto",
-                    "--quiet",
-                    "--cov=google",
-                    "--cov-append",
-                    f"--cov-fail-under={str(fail_under)}",
-                    path.join("tests", "unit"),
-                ]
-            ),
-        )
+    session.run(
+        "py.test",
+        *(
+            session.posargs
+            or [
+                "-n=auto",
+                "--quiet",
+                "--cov=google",
+                "--cov-append",
+                f"--cov-fail-under={str(fail_under)}",
+                path.join("tests", "unit"),
+            ]
+        ),
+    )
 
 
 @nox.session(python=ALL_PYTHON)
diff --git a/requirements.in b/requirements.in
index d6a1c8d6f1..2a9d7bb2cd 100644
--- a/requirements.in
+++ b/requirements.in
@@ -3,7 +3,7 @@ google-api-core
 googleapis-common-protos
 jinja2
 MarkupSafe
-protobuf
+protobuf>=4.25.8
 pypandoc
 PyYAML
 grpc-google-iam-v1
diff --git a/requirements.txt b/requirements.txt
index dfba7dd8d8..10f053daf9 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,8 +1,8 @@
 #
-# This file is autogenerated by pip-compile with Python 3.10
+# This file is autogenerated by pip-compile with Python 3.11
 # by the following command:
 #
-#    pip-compile --allow-unsafe --generate-hashes requirements.in
+#    pip-compile --allow-unsafe --generate-hashes --output-file=requirements.txt requirements.in
 #
 aiohappyeyeballs==2.6.1 \
     --hash=sha256:c3f9d0113123803ccadfdf3f0faa505bc78e6a72d1cc4806cbd719826e943558 \
@@ -134,18 +134,10 @@ aiosignal==1.4.0 \
     --hash=sha256:053243f8b92b990551949e63930a839ff0cf0b0ebbe0597b0f3fb19e1a0fe82e \
     --hash=sha256:f47eecd9468083c2029cc99945502cb7708b082c232f9aca65da147157b251c7
     # via aiohttp
-async-timeout==5.0.1 \
-    --hash=sha256:39e3809566ff85354557ec2398b55e096c8364bacac9405a7a1fa429e77fe76c \
-    --hash=sha256:d9321a7a3d5a6a5e187e824d2fa0793ce379a202935782d555d6e9d2735677d3
-    # via aiohttp
 attrs==25.4.0 \
     --hash=sha256:16d5969b87f0859ef33a48b35d55ac1be6e42ae49d5e853b597db70c35c57e11 \
     --hash=sha256:adcf7e2a1fb3b36ac48d97835bb6d8ade15b8dcce26aba8bf1d14847b57a3373
     # via aiohttp
-backports-asyncio-runner==1.2.0 \
-    --hash=sha256:0da0a936a8aeb554eccb426dc55af3ba63bcdc69fa1a600b5bb305413a4477b5 \
-    --hash=sha256:a5aa7b2b7d8f8bfcaa2b57313f70792df84e32a2a746f585213373f900b42162
-    # via pytest-asyncio
 cachetools==6.2.1 \
     --hash=sha256:09868944b6dde876dfd44e1d47e18484541eaf12f26f29b7af91b26cc892d701 \
     --hash=sha256:3f391e4bd8f8bf0931169baf7456cc822705f4e2a31f840d218f445b9a854201
@@ -273,10 +265,6 @@ click==8.3.0 \
     --hash=sha256:9b9f285302c6e3064f4330c05f05b81945b2a39544279343e6e7c5f27a9baddc \
     --hash=sha256:e7b8232224eba16f4ebe410c25ced9f7875cb5f3263ffc93cc3e8da705e229c4
     # via -r requirements.in
-exceptiongroup==1.3.0 \
-    --hash=sha256:4d111e6e0c13d0644cad6ddaa7ed0261a0b36971f6d23e7ec9b4b9097da78a10 \
-    --hash=sha256:b241f5885f560bc56a59ee63ca4c6a8bfa46ae4ad651af316d4e81817bb9fd88
-    # via pytest
 frozenlist==1.8.0 \
     --hash=sha256:0325024fe97f94c41c08872db482cf8ac4800d80e79222c6b0b7b162d5b13686 \
     --hash=sha256:032efa2674356903cd0261c4317a561a6850f3ac864a63fc1583147fb05a79b0 \
@@ -1090,58 +1078,12 @@ rsa==4.9.1 \
     --hash=sha256:68635866661c6836b8d39430f97a996acbd61bfa49406748ea243539fe239762 \
     --hash=sha256:e7bdbfdb5497da4c07dfd35530e1a902659db6ff241e39d9953cad06ebd0ae75
     # via google-auth
-tomli==2.3.0 \
-    --hash=sha256:00b5f5d95bbfc7d12f91ad8c593a1659b6387b43f054104cda404be6bda62456 \
-    --hash=sha256:0a154a9ae14bfcf5d8917a59b51ffd5a3ac1fd149b71b47a3a104ca4edcfa845 \
-    --hash=sha256:0c95ca56fbe89e065c6ead5b593ee64b84a26fca063b5d71a1122bf26e533999 \
-    --hash=sha256:0eea8cc5c5e9f89c9b90c4896a8deefc74f518db5927d0e0e8d4a80953d774d0 \
-    --hash=sha256:1cb4ed918939151a03f33d4242ccd0aa5f11b3547d0cf30f7c74a408a5b99878 \
-    --hash=sha256:4021923f97266babc6ccab9f5068642a0095faa0a51a246a6a02fccbb3514eaf \
-    --hash=sha256:4c2ef0244c75aba9355561272009d934953817c49f47d768070c3c94355c2aa3 \
-    --hash=sha256:4dc4ce8483a5d429ab602f111a93a6ab1ed425eae3122032db7e9acf449451be \
-    --hash=sha256:4f195fe57ecceac95a66a75ac24d9d5fbc98ef0962e09b2eddec5d39375aae52 \
-    --hash=sha256:5192f562738228945d7b13d4930baffda67b69425a7f0da96d360b0a3888136b \
-    --hash=sha256:5e01decd096b1530d97d5d85cb4dff4af2d8347bd35686654a004f8dea20fc67 \
-    --hash=sha256:64be704a875d2a59753d80ee8a533c3fe183e3f06807ff7dc2232938ccb01549 \
-    --hash=sha256:70a251f8d4ba2d9ac2542eecf008b3c8a9fc5c3f9f02c56a9d7952612be2fdba \
-    --hash=sha256:73ee0b47d4dad1c5e996e3cd33b8a76a50167ae5f96a2607cbe8cc773506ab22 \
-    --hash=sha256:74bf8464ff93e413514fefd2be591c3b0b23231a77f901db1eb30d6f712fc42c \
-    --hash=sha256:792262b94d5d0a466afb5bc63c7daa9d75520110971ee269152083270998316f \
-    --hash=sha256:7b0882799624980785240ab732537fcfc372601015c00f7fc367c55308c186f6 \
-    --hash=sha256:883b1c0d6398a6a9d29b508c331fa56adbcdff647f6ace4dfca0f50e90dfd0ba \
-    --hash=sha256:88bd15eb972f3664f5ed4b57c1634a97153b4bac4479dcb6a495f41921eb7f45 \
-    --hash=sha256:8a35dd0e643bb2610f156cca8db95d213a90015c11fee76c946aa62b7ae7e02f \
-    --hash=sha256:940d56ee0410fa17ee1f12b817b37a4d4e4dc4d27340863cc67236c74f582e77 \
-    --hash=sha256:97d5eec30149fd3294270e889b4234023f2c69747e555a27bd708828353ab606 \
-    --hash=sha256:a0e285d2649b78c0d9027570d4da3425bdb49830a6156121360b3f8511ea3441 \
-    --hash=sha256:a1f7f282fe248311650081faafa5f4732bdbfef5d45fe3f2e702fbc6f2d496e0 \
-    --hash=sha256:a4ea38c40145a357d513bffad0ed869f13c1773716cf71ccaa83b0fa0cc4e42f \
-    --hash=sha256:a56212bdcce682e56b0aaf79e869ba5d15a6163f88d5451cbde388d48b13f530 \
-    --hash=sha256:ad805ea85eda330dbad64c7ea7a4556259665bdf9d2672f5dccc740eb9d3ca05 \
-    --hash=sha256:b273fcbd7fc64dc3600c098e39136522650c49bca95df2d11cf3b626422392c8 \
-    --hash=sha256:b5870b50c9db823c595983571d1296a6ff3e1b88f734a4c8f6fc6188397de005 \
-    --hash=sha256:b74a0e59ec5d15127acdabd75ea17726ac4c5178ae51b85bfe39c4f8a278e879 \
-    --hash=sha256:be71c93a63d738597996be9528f4abe628d1adf5e6eb11607bc8fe1a510b5dae \
-    --hash=sha256:c22a8bf253bacc0cf11f35ad9808b6cb75ada2631c2d97c971122583b129afbc \
-    --hash=sha256:c4665508bcbac83a31ff8ab08f424b665200c0e1e645d2bd9ab3d3e557b6185b \
-    --hash=sha256:c5f3ffd1e098dfc032d4d3af5c0ac64f6d286d98bc148698356847b80fa4de1b \
-    --hash=sha256:cebc6fe843e0733ee827a282aca4999b596241195f43b4cc371d64fc6639da9e \
-    --hash=sha256:d1381caf13ab9f300e30dd8feadb3de072aeb86f1d34a8569453ff32a7dea4bf \
-    --hash=sha256:d7d86942e56ded512a594786a5ba0a5e521d02529b3826e7761a05138341a2ac \
-    --hash=sha256:e31d432427dcbf4d86958c184b9bfd1e96b5b71f8eb17e6d02531f434fd335b8 \
-    --hash=sha256:e95b1af3c5b07d9e643909b5abbec77cd9f1217e6d0bca72b0234736b9fb1f1b \
-    --hash=sha256:f85209946d1fe94416debbb88d00eb92ce9cd5266775424ff81bc959e001acaf \
-    --hash=sha256:feb0dacc61170ed7ab602d3d972a58f14ee3ee60494292d384649a3dc38ef463 \
-    --hash=sha256:ff72b71b5d10d22ecb084d345fc26f42b5143c5533db5e2eaba7d2d335358876
-    # via pytest
 typing-extensions==4.15.0 \
     --hash=sha256:0cea48d173cc12fa28ecabc3b837ea3cf6f38c6d1136f85cbaaf598984861466 \
     --hash=sha256:f0fa19c6845758ab08074a0cfa8b7aecb71c999ca73d62883bc25cc018c4e548
     # via
     #   aiosignal
-    #   exceptiongroup
     #   grpcio
-    #   multidict
     #   pytest-asyncio
 urllib3==2.5.0 \
     --hash=sha256:3fc47733c7e419d4bc3f6b3dc2b4f890bb743906a30d56ba4a5bfa4bbff92760 \
diff --git a/setup.py b/setup.py
index c02c9af9c0..d45842faae 100644
--- a/setup.py
+++ b/setup.py
@@ -35,7 +35,7 @@
     # https://jinja.palletsprojects.com/en/3.0.x/templates/#jinja-filters.map
     # https://jinja.palletsprojects.com/en/2.11.x/changelog/#version-2-11-0
     "jinja2 >= 2.11",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
     "pypandoc >= 1.4",
     "PyYAML >= 5.1.1",
     "grpc-google-iam-v1 >= 0.14.0, < 1.0.0",
@@ -70,8 +70,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -83,7 +81,7 @@
         "Topic :: Software Development :: Libraries :: Python Modules",
     ],
     platforms="Posix; MacOS X",
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     include_package_data=True,
     zip_safe=False,
diff --git a/tests/integration/goldens/asset/noxfile.py b/tests/integration/goldens/asset/noxfile.py
index c0c32cce8d..325ba9b28a 100755
--- a/tests/integration/goldens/asset/noxfile.py
+++ b/tests/integration/goldens/asset/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/asset/setup.py b/tests/integration/goldens/asset/setup.py
index db0a03c590..c8118e1a4a 100755
--- a/tests/integration/goldens/asset/setup.py
+++ b/tests/integration/goldens/asset/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
     "google-cloud-access-context-manager >= 0.1.2, <1.0.0",
     "google-cloud-os-config >= 1.0.0, <2.0.0",
     "grpc-google-iam-v1 >= 0.14.0, <1.0.0",
@@ -83,8 +83,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -96,7 +94,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/asset/testing/constraints-3.7.txt b/tests/integration/goldens/asset/testing/constraints-3.7.txt
deleted file mode 100755
index 45771b18c6..0000000000
--- a/tests/integration/goldens/asset/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,15 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
-google-cloud-access-context-manager==0.1.2
-google-cloud-os-config==1.0.0
-grpc-google-iam-v1==0.14.0
diff --git a/tests/integration/goldens/asset/testing/constraints-3.8.txt b/tests/integration/goldens/asset/testing/constraints-3.8.txt
deleted file mode 100755
index 763d545abe..0000000000
--- a/tests/integration/goldens/asset/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,11 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
-google-cloud-access-context-manager
-google-cloud-os-config
-grpc-google-iam-v1
diff --git a/tests/integration/goldens/asset/testing/constraints-3.9.txt b/tests/integration/goldens/asset/testing/constraints-3.9.txt
index 763d545abe..1d4be8919b 100755
--- a/tests/integration/goldens/asset/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/asset/testing/constraints-3.9.txt
@@ -1,11 +1,16 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
-google-cloud-access-context-manager
-google-cloud-os-config
-grpc-google-iam-v1
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
+google-cloud-access-context-manager==0.1.2
+google-cloud-os-config==1.0.0
+grpc-google-iam-v1==0.14.0
diff --git a/tests/integration/goldens/credentials/noxfile.py b/tests/integration/goldens/credentials/noxfile.py
index 488c013ac7..49a19c4761 100755
--- a/tests/integration/goldens/credentials/noxfile.py
+++ b/tests/integration/goldens/credentials/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/credentials/setup.py b/tests/integration/goldens/credentials/setup.py
index eaba6dcd0c..759cd11bc5 100755
--- a/tests/integration/goldens/credentials/setup.py
+++ b/tests/integration/goldens/credentials/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
 ]
 extras = {
 }
@@ -80,8 +80,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -93,7 +91,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/credentials/testing/constraints-3.7.txt b/tests/integration/goldens/credentials/testing/constraints-3.7.txt
deleted file mode 100755
index 5d29dea386..0000000000
--- a/tests/integration/goldens/credentials/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
diff --git a/tests/integration/goldens/credentials/testing/constraints-3.8.txt b/tests/integration/goldens/credentials/testing/constraints-3.8.txt
deleted file mode 100755
index 93e6826f2a..0000000000
--- a/tests/integration/goldens/credentials/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
diff --git a/tests/integration/goldens/credentials/testing/constraints-3.9.txt b/tests/integration/goldens/credentials/testing/constraints-3.9.txt
index 93e6826f2a..571c4f68f9 100755
--- a/tests/integration/goldens/credentials/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/credentials/testing/constraints-3.9.txt
@@ -1,8 +1,13 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
diff --git a/tests/integration/goldens/eventarc/noxfile.py b/tests/integration/goldens/eventarc/noxfile.py
index 228dccbbed..8ef15b00a0 100755
--- a/tests/integration/goldens/eventarc/noxfile.py
+++ b/tests/integration/goldens/eventarc/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/eventarc/setup.py b/tests/integration/goldens/eventarc/setup.py
index 8f8887b4d5..eae607c5b2 100755
--- a/tests/integration/goldens/eventarc/setup.py
+++ b/tests/integration/goldens/eventarc/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
     "grpc-google-iam-v1 >= 0.14.0, <1.0.0",
 ]
 extras = {
@@ -81,8 +81,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -94,7 +92,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/eventarc/testing/constraints-3.7.txt b/tests/integration/goldens/eventarc/testing/constraints-3.7.txt
deleted file mode 100755
index 5b1ee6c35a..0000000000
--- a/tests/integration/goldens/eventarc/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
-grpc-google-iam-v1==0.14.0
diff --git a/tests/integration/goldens/eventarc/testing/constraints-3.8.txt b/tests/integration/goldens/eventarc/testing/constraints-3.8.txt
deleted file mode 100755
index ef1c92ffff..0000000000
--- a/tests/integration/goldens/eventarc/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,9 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
-grpc-google-iam-v1
diff --git a/tests/integration/goldens/eventarc/testing/constraints-3.9.txt b/tests/integration/goldens/eventarc/testing/constraints-3.9.txt
index ef1c92ffff..14916e95fd 100755
--- a/tests/integration/goldens/eventarc/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/eventarc/testing/constraints-3.9.txt
@@ -1,9 +1,14 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
-grpc-google-iam-v1
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
+grpc-google-iam-v1==0.14.0
diff --git a/tests/integration/goldens/logging/noxfile.py b/tests/integration/goldens/logging/noxfile.py
index 106be18e72..8bc0a7bc8c 100755
--- a/tests/integration/goldens/logging/noxfile.py
+++ b/tests/integration/goldens/logging/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/logging/setup.py b/tests/integration/goldens/logging/setup.py
index cb6015c69b..2464aa281a 100755
--- a/tests/integration/goldens/logging/setup.py
+++ b/tests/integration/goldens/logging/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
 ]
 extras = {
 }
@@ -80,8 +80,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -93,7 +91,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/logging/testing/constraints-3.7.txt b/tests/integration/goldens/logging/testing/constraints-3.7.txt
deleted file mode 100755
index 5d29dea386..0000000000
--- a/tests/integration/goldens/logging/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
diff --git a/tests/integration/goldens/logging/testing/constraints-3.8.txt b/tests/integration/goldens/logging/testing/constraints-3.8.txt
deleted file mode 100755
index 93e6826f2a..0000000000
--- a/tests/integration/goldens/logging/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
diff --git a/tests/integration/goldens/logging/testing/constraints-3.9.txt b/tests/integration/goldens/logging/testing/constraints-3.9.txt
index 93e6826f2a..571c4f68f9 100755
--- a/tests/integration/goldens/logging/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/logging/testing/constraints-3.9.txt
@@ -1,8 +1,13 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
diff --git a/tests/integration/goldens/logging_internal/noxfile.py b/tests/integration/goldens/logging_internal/noxfile.py
index 106be18e72..8bc0a7bc8c 100755
--- a/tests/integration/goldens/logging_internal/noxfile.py
+++ b/tests/integration/goldens/logging_internal/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/logging_internal/setup.py b/tests/integration/goldens/logging_internal/setup.py
index cb6015c69b..2464aa281a 100755
--- a/tests/integration/goldens/logging_internal/setup.py
+++ b/tests/integration/goldens/logging_internal/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
 ]
 extras = {
 }
@@ -80,8 +80,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -93,7 +91,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/logging_internal/testing/constraints-3.7.txt b/tests/integration/goldens/logging_internal/testing/constraints-3.7.txt
deleted file mode 100755
index 5d29dea386..0000000000
--- a/tests/integration/goldens/logging_internal/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
diff --git a/tests/integration/goldens/logging_internal/testing/constraints-3.8.txt b/tests/integration/goldens/logging_internal/testing/constraints-3.8.txt
deleted file mode 100755
index 93e6826f2a..0000000000
--- a/tests/integration/goldens/logging_internal/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
diff --git a/tests/integration/goldens/logging_internal/testing/constraints-3.9.txt b/tests/integration/goldens/logging_internal/testing/constraints-3.9.txt
index 93e6826f2a..571c4f68f9 100755
--- a/tests/integration/goldens/logging_internal/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/logging_internal/testing/constraints-3.9.txt
@@ -1,8 +1,13 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
diff --git a/tests/integration/goldens/redis/noxfile.py b/tests/integration/goldens/redis/noxfile.py
index 490680cd3d..8af6c70603 100755
--- a/tests/integration/goldens/redis/noxfile.py
+++ b/tests/integration/goldens/redis/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/redis/setup.py b/tests/integration/goldens/redis/setup.py
index 026674b2d3..878aac76e0 100755
--- a/tests/integration/goldens/redis/setup.py
+++ b/tests/integration/goldens/redis/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
 ]
 extras = {
     "async_rest": [
@@ -84,8 +84,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -97,7 +95,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/redis/testing/constraints-3.7.txt b/tests/integration/goldens/redis/testing/constraints-3.7.txt
deleted file mode 100755
index 5d29dea386..0000000000
--- a/tests/integration/goldens/redis/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
diff --git a/tests/integration/goldens/redis/testing/constraints-3.8.txt b/tests/integration/goldens/redis/testing/constraints-3.8.txt
deleted file mode 100755
index 93e6826f2a..0000000000
--- a/tests/integration/goldens/redis/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
diff --git a/tests/integration/goldens/redis/testing/constraints-3.9.txt b/tests/integration/goldens/redis/testing/constraints-3.9.txt
index 93e6826f2a..571c4f68f9 100755
--- a/tests/integration/goldens/redis/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/redis/testing/constraints-3.9.txt
@@ -1,8 +1,13 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8
diff --git a/tests/integration/goldens/redis_selective/noxfile.py b/tests/integration/goldens/redis_selective/noxfile.py
index 490680cd3d..8af6c70603 100755
--- a/tests/integration/goldens/redis_selective/noxfile.py
+++ b/tests/integration/goldens/redis_selective/noxfile.py
@@ -39,8 +39,6 @@
     FORMAT_PATHS.append("samples")
 
 ALL_PYTHON = [
-    "3.7",
-    "3.8",
     "3.9",
     "3.10",
     "3.11",
diff --git a/tests/integration/goldens/redis_selective/setup.py b/tests/integration/goldens/redis_selective/setup.py
index 026674b2d3..878aac76e0 100755
--- a/tests/integration/goldens/redis_selective/setup.py
+++ b/tests/integration/goldens/redis_selective/setup.py
@@ -39,7 +39,7 @@
     release_status = "Development Status :: 5 - Production/Stable"
 
 dependencies = [
-    "google-api-core[grpc] >= 1.34.1, <3.0.0,!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,!=2.5.*,!=2.6.*,!=2.7.*,!=2.8.*,!=2.9.*,!=2.10.*",
+    "google-api-core[grpc] >= 2.11.0, <3.0.0",
     # Exclude incompatible versions of `google-auth`
     # See https://github.com/googleapis/google-cloud-python/issues/12364
     "google-auth >= 2.14.1, <3.0.0,!=2.24.0,!=2.25.0",
@@ -47,7 +47,7 @@
     "grpcio >= 1.75.1, < 2.0.0; python_version >= '3.14'",
     "proto-plus >= 1.22.3, <2.0.0",
     "proto-plus >= 1.25.0, <2.0.0; python_version >= '3.13'",
-    "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+    "protobuf >= 4.25.8, <7.0.0",
 ]
 extras = {
     "async_rest": [
@@ -84,8 +84,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -97,7 +95,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.7",
+    python_requires=">=3.9",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,
diff --git a/tests/integration/goldens/redis_selective/testing/constraints-3.7.txt b/tests/integration/goldens/redis_selective/testing/constraints-3.7.txt
deleted file mode 100755
index 5d29dea386..0000000000
--- a/tests/integration/goldens/redis_selective/testing/constraints-3.7.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-# This constraints file is used to check that lower bounds
-# are correct in setup.py
-# List all library dependencies and extras in this file.
-# Pin the version to the lower bound.
-# e.g., if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
-# Then this file should have google-cloud-foo==1.14.0
-google-api-core==1.34.1
-google-auth==2.14.1
-# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
-# Add the minimum supported version of grpcio to constraints files
-proto-plus==1.22.3
-protobuf==3.20.2
diff --git a/tests/integration/goldens/redis_selective/testing/constraints-3.8.txt b/tests/integration/goldens/redis_selective/testing/constraints-3.8.txt
deleted file mode 100755
index 93e6826f2a..0000000000
--- a/tests/integration/goldens/redis_selective/testing/constraints-3.8.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
diff --git a/tests/integration/goldens/redis_selective/testing/constraints-3.9.txt b/tests/integration/goldens/redis_selective/testing/constraints-3.9.txt
index 93e6826f2a..571c4f68f9 100755
--- a/tests/integration/goldens/redis_selective/testing/constraints-3.9.txt
+++ b/tests/integration/goldens/redis_selective/testing/constraints-3.9.txt
@@ -1,8 +1,13 @@
 # -*- coding: utf-8 -*-
-# This constraints file is required for unit tests.
-# List all library dependencies and extras in this file.
-google-api-core
-google-auth
-grpcio
-proto-plus
-protobuf
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List all library dependencies and extras in this file,
+# pinning their versions to their lower bounds.
+# For example, if setup.py has "google-cloud-foo >= 1.14.0, < 2.0.0",
+# then this file should have google-cloud-foo==1.14.0
+google-api-core==2.11.0
+google-auth==2.35.0
+# TODO(https://github.com/googleapis/gapic-generator-python/issues/2453)
+# Add the minimum supported version of grpcio to constraints files
+proto-plus==1.22.3
+protobuf==4.25.8