diff --git a/providers/anthropic/README.rst b/providers/anthropic/README.rst
index eea65725b0672..aa2a8a925e3ad 100644
--- a/providers/anthropic/README.rst
+++ b/providers/anthropic/README.rst
@@ -52,13 +52,13 @@ The package supports the following python versions: 3.10,3.11,3.12,3.13,3.14
 Requirements
 ------------
 
-==========================================  ==================
+==========================================  ====================
 PIP package                                 Version required
-==========================================  ==================
+==========================================  ====================
 ``apache-airflow``                          ``>=3.0.0``
 ``apache-airflow-providers-common-compat``  ``>=1.12.0``
-``anthropic``                               ``>=0.121.0``
-==========================================  ==================
+``anthropic``                               ``>=0.121.0,<1.0.0``
+==========================================  ====================
 
 Optional dependencies
 ----------------------
diff --git a/providers/anthropic/docs/index.rst b/providers/anthropic/docs/index.rst
index f6c79ccb07c2c..fd9c4ef97f7c6 100644
--- a/providers/anthropic/docs/index.rst
+++ b/providers/anthropic/docs/index.rst
@@ -133,13 +133,13 @@ Requirements
 
 The minimum Apache Airflow version supported by this provider distribution is ``3.0.0``.
 
-==========================================  ==================
+==========================================  ====================
 PIP package                                 Version required
-==========================================  ==================
+==========================================  ====================
 ``apache-airflow``                          ``>=3.0.0``
 ``apache-airflow-providers-common-compat``  ``>=1.12.0``
-``anthropic``                               ``>=0.121.0``
-==========================================  ==================
+``anthropic``                               ``>=0.121.0,<1.0.0``
+==========================================  ====================
 
 Optional dependencies
 ---------------------
@@ -152,13 +152,13 @@ Install them when installing from PyPI. For example:
     pip install apache-airflow-providers-anthropic[bedrock]
 
 
-===========  ===============================
+===========  ======================================
 Extra        Dependencies
-===========  ===============================
-``bedrock``  ``anthropic[bedrock]>=0.121.0``
-``vertex``   ``anthropic[vertex]>=0.121.0``
-``aws``      ``anthropic[aws]>=0.121.0``
-===========  ===============================
+===========  ======================================
+``bedrock``  ``anthropic[bedrock]>=0.121.0,<1.0.0``
+``vertex``   ``anthropic[vertex]>=0.121.0,<1.0.0``
+``aws``      ``anthropic[aws]>=0.121.0,<1.0.0``
+===========  ======================================
 
 Downloading official packages
 -----------------------------
diff --git a/providers/anthropic/pyproject.toml b/providers/anthropic/pyproject.toml
index 41286bea7b279..a967811f13ff8 100644
--- a/providers/anthropic/pyproject.toml
+++ b/providers/anthropic/pyproject.toml
@@ -66,15 +66,19 @@ dependencies = [
     # reason happens to work further back -- older clients mis-build the discriminated
     # union into the wrong variant class while preserving ``.type`` -- but only with
     # response validation left non-strict, so it is not something to depend on.
-    "anthropic>=0.121.0",
+    # anthropic 1.0.0 replaces httpx with httpx2 and is a major release the provider
+    # has not been validated against. Remove the <1.0.0 cap (here and in the extras
+    # below) after migrating to the 1.x SDK;
+    # tracked at https://github.com/apache/airflow/issues/72071
+    "anthropic>=0.121.0,<1.0.0",
 ]
 
 # The optional dependencies should be modified in place in the generated file
 # Any change in the dependencies is preserved when the file is regenerated
 [project.optional-dependencies]
-"bedrock" = ["anthropic[bedrock]>=0.121.0"]
-"vertex" = ["anthropic[vertex]>=0.121.0"]
-"aws" = ["anthropic[aws]>=0.121.0"]
+"bedrock" = ["anthropic[bedrock]>=0.121.0,<1.0.0"]
+"vertex" = ["anthropic[vertex]>=0.121.0,<1.0.0"]
+"aws" = ["anthropic[aws]>=0.121.0,<1.0.0"]
 
 [dependency-groups]
 dev = [
diff --git a/uv.lock b/uv.lock
index 8e2e61c1860d7..243691d0e61fe 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1097,20 +1097,21 @@ wheels = [
 
 [[package]]
 name = "anthropic"
-version = "1.0.0"
+version = "0.125.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "anyio" },
+    { name = "distro" },
     { name = "docstring-parser" },
-    { name = "httpx2" },
+    { name = "httpx" },
     { name = "jiter" },
     { name = "pydantic" },
     { name = "sniffio" },
     { name = "typing-extensions" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/25/aa/4978e58035bd6c638c7b483450a68b7ef2d732ab78885e27bb9db0cff1a2/anthropic-1.0.0.tar.gz", hash = "sha256:42be3c97604af7252c5898413aee076ace6c46e9bca0d0d90ceb77c7d3719027", size = 1077769, upload-time = "2026-08-20T19:59:00.565Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/62/f8/6f0560884b5363848347bd640b6c1d04abc25e7aa61787a232f790c6b60a/anthropic-0.125.0.tar.gz", hash = "sha256:e0cdd336580cb7411c1cdab69f80973e9bf4bff7f8e08141811d46307d45c682", size = 1112593, upload-time = "2026-08-19T22:00:42.837Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/ad/5b/db4a854aebf5d33a5ab714c46af6eb85ee44f390ed29b7b325c00b9f11ed/anthropic-1.0.0-py3-none-any.whl", hash = "sha256:32dd52e9e1d774393b27182f451398ba4262287a4d0eab30887f89f1481b3ae4", size = 1171725, upload-time = "2026-08-20T19:58:58.725Z" },
+    { url = "https://files.pythonhosted.org/packages/2f/1a/b1bd30cda3790557e8791bec5922a6ec8fabb6fa8b008c76a39cf7be6152/anthropic-0.125.0-py3-none-any.whl", hash = "sha256:3486013602eca76d8b12540764e53654f02cf4951110bca86cf06e67428a9f21", size = 1184067, upload-time = "2026-08-19T22:00:44.596Z" },
 ]
 
 [package.optional-dependencies]
@@ -3441,10 +3442,10 @@ docs = [
 
 [package.metadata]
 requires-dist = [
-    { name = "anthropic", specifier = ">=0.121.0" },
-    { name = "anthropic", extras = ["aws"], marker = "extra == 'aws'", specifier = ">=0.121.0" },
-    { name = "anthropic", extras = ["bedrock"], marker = "extra == 'bedrock'", specifier = ">=0.121.0" },
-    { name = "anthropic", extras = ["vertex"], marker = "extra == 'vertex'", specifier = ">=0.121.0" },
+    { name = "anthropic", specifier = ">=0.121.0,<1.0.0" },
+    { name = "anthropic", extras = ["aws"], marker = "extra == 'aws'", specifier = ">=0.121.0,<1.0.0" },
+    { name = "anthropic", extras = ["bedrock"], marker = "extra == 'bedrock'", specifier = ">=0.121.0,<1.0.0" },
+    { name = "anthropic", extras = ["vertex"], marker = "extra == 'vertex'", specifier = ">=0.121.0,<1.0.0" },
     { name = "apache-airflow", editable = "." },
     { name = "apache-airflow-providers-common-compat", editable = "providers/common/compat" },
 ]