diff --git a/src/main/java/io/cryostat/net/web/http/api/beta/MatchExpressionsPostHandler.java b/src/main/java/io/cryostat/net/web/http/api/beta/MatchExpressionsPostHandler.java
index 683ffbc8af..3af88f5ad7 100644
--- a/src/main/java/io/cryostat/net/web/http/api/beta/MatchExpressionsPostHandler.java
+++ b/src/main/java/io/cryostat/net/web/http/api/beta/MatchExpressionsPostHandler.java
@@ -159,7 +159,7 @@ public IntermediateResponse<MatchedMatchExpression> handle(RequestParameters par
             throw new ApiException(400, "Unable to parse JSON", e);
         } catch (RollbackException e) {
             if (ExceptionUtils.indexOfType(e, ConstraintViolationException.class) >= 0) {
-                throw new ApiException(400, "Duplicate matchExpression", e);
+                throw new ApiException(409, "Duplicate matchExpression", e);
             }
             throw new ApiException(500, e);
         } catch (MatchExpressionValidationException e) {
diff --git a/src/main/java/io/cryostat/net/web/http/api/v2/CredentialsPostHandler.java b/src/main/java/io/cryostat/net/web/http/api/v2/CredentialsPostHandler.java
index 98d613edb4..a430ac1c44 100644
--- a/src/main/java/io/cryostat/net/web/http/api/v2/CredentialsPostHandler.java
+++ b/src/main/java/io/cryostat/net/web/http/api/v2/CredentialsPostHandler.java
@@ -144,7 +144,7 @@ public IntermediateResponse<Void> handle(RequestParameters params) throws ApiExc
                     .body(null);
         } catch (RollbackException e) {
             if (ExceptionUtils.indexOfType(e, ConstraintViolationException.class) >= 0) {
-                throw new ApiException(400, "Duplicate matchExpression", e);
+                throw new ApiException(409, "Duplicate matchExpression", e);
             }
             throw new ApiException(500, e);
         } catch (MatchExpressionValidationException e) {