diff --git a/site/xunit.analyzers/rules/index.md b/site/xunit.analyzers/rules/index.md
index d890f75..ea7760e 100644
--- a/site/xunit.analyzers/rules/index.md
+++ b/site/xunit.analyzers/rules/index.md
@@ -89,6 +89,8 @@ Tag                                                                      | Meani
 | [xUnit1067](/xunit.analyzers/rules/xUnit1067) | ::v2::{.label .label-version-True} ::v3::{.label .label-version-True} ::AOT::{.label .label-version-True}   | ::E::{.label .label-Error .label-Fixed}   | There is no matching MemberData method argument
 | [xUnit1068](/xunit.analyzers/rules/xUnit1068) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-False} ::AOT::{.label .label-version-True} | ::E::{.label .label-Error .label-Fixed}   | MemberData cannot point to an open generic type
 | [xUnit1069](/xunit.analyzers/rules/xUnit1069) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True} ::AOT::{.label .label-version-True}  | ::W::{.label .label-Warning .label-Fixed} | Test methods with a Timeout should reference TestContext.Current.CancellationToken
+| [xUnit1070](/xunit.analyzers/rules/xUnit1070) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True} ::AOT::{.label .label-version-True}  | ::E::{.label .label-Error .label-Fixed}   | Cultured test methods cannot have null cultures
+| [xUnit1071](/xunit.analyzers/rules/xUnit1071) | ::v2::{.label .label-version-False} ::v3::{.label .label-version-True} ::AOT::{.label .label-version-True}  | ::W::{.label .label-Warning .label-Fixed} | Cultured test methods should not have duplicate cultures
 
 ## Assertion Analyzers (2xxx)
 
diff --git a/site/xunit.analyzers/rules/xUnit1070.md b/site/xunit.analyzers/rules/xUnit1070.md
new file mode 100644
index 0000000..d29d26c
--- /dev/null
+++ b/site/xunit.analyzers/rules/xUnit1070.md
@@ -0,0 +1,49 @@
+---
+analyzer: true
+title: xUnit1070
+description: Cultured test methods cannot have null cultures
+severity: Error
+v2: false
+v3: true
+aot: true
+---
+
+## Cause
+
+A violation of this rule occurs when one of the cultures declared on a cultured test is `null`.
+
+## Reason for rule
+
+Cultured test methods run one test for each declared culture, so every culture must be a valid culture name. A `null` culture cannot be turned into a culture, so the test framework fails with an error when it discovers the test.
+
+## How to fix violations
+
+To fix a violation of this rule, replace the `null` value with a valid culture name, or remove it.
+
+## Examples
+
+### Violates
+
+```csharp
+using Xunit;
+
+public class xUnit1070
+{
+    [CulturedFact(["en-US", null])]
+    public void FactMethod()
+    { }
+}
+```
+
+### Does not violate
+
+```csharp
+using Xunit;
+
+public class xUnit1070
+{
+    [CulturedFact(["en-US", "fr-FR"])]
+    public void FactMethod()
+    { }
+}
+```
diff --git a/site/xunit.analyzers/rules/xUnit1071.md b/site/xunit.analyzers/rules/xUnit1071.md
new file mode 100644
index 0000000..33c6bda
--- /dev/null
+++ b/site/xunit.analyzers/rules/xUnit1071.md
@@ -0,0 +1,49 @@
+---
+analyzer: true
+title: xUnit1071
+description: Cultured test methods should not have duplicate cultures
+severity: Warning
+v2: false
+v3: true
+aot: true
+---
+
+## Cause
+
+A violation of this rule occurs when the same culture is declared more than once on a cultured test. Culture names are compared case-insensitively, so `"en-US"` and `"en-us"` count as duplicates.
+
+## Reason for rule
+
+Cultured test methods run one test for each declared culture. A duplicated culture runs the same test more than once under the same culture, which adds no coverage and produces test cases with the same display name and unique ID.
+
+## How to fix violations
+
+To fix a violation of this rule, remove the duplicated culture.
+
+## Examples
+
+### Violates
+
+```csharp
+using Xunit;
+
+public class xUnit1071
+{
+    [CulturedFact(["en-US", "fr-FR", "en-US"])]
+    public void FactMethod()
+    { }
+}
+```
+
+### Does not violate
+
+```csharp
+using Xunit;
+
+public class xUnit1071
+{
+    [CulturedFact(["en-US", "fr-FR"])]
+    public void FactMethod()
+    { }
+}
+```