diff --git a/modules/openapi-generator/src/main/resources/typescript-angular/queryParams.mustache b/modules/openapi-generator/src/main/resources/typescript-angular/queryParams.mustache
index 4076c1140c83..978fde0d2ea2 100644
--- a/modules/openapi-generator/src/main/resources/typescript-angular/queryParams.mustache
+++ b/modules/openapi-generator/src/main/resources/typescript-angular/queryParams.mustache
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/query.params.ts b/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/query.params.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/query.params.ts b/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/query.params.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-form/query.params.ts b/samples/client/others/typescript-angular-v20/builds/query-param-form/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-form/query.params.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-form/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-json/query.params.ts b/samples/client/others/typescript-angular-v20/builds/query-param-json/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-json/query.params.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-json/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_form.spec.ts b/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_form.spec.ts
index d0994e2a8822..6397a53f753a 100644
--- a/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_form.spec.ts
+++ b/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_form.spec.ts
@@ -7,6 +7,11 @@ import {DefaultService, Filter, provideApi} from '@swagger/typescript-angular-qu
 const ids: number[] = [4, 5];
 const filter: Filter = {name: 'John', age: 37, nicknames: ['Joe', 'Joey']};
 const filterWithSpecialCharacters: Filter = {name: 'Éléonore &,|+', age: 42, nicknames: ['Elé', 'Ellie']};
+const filterWithUndefined: Filter = {name: 'John', age: undefined, nicknames: ['Joe']};
+const filterAllUndefined: Filter = {name: undefined, age: undefined, nicknames: undefined};
+const filterWithNullItems = {name: 'John', nicknames: ['Joe', null, undefined]} as unknown as Filter;
+const filterWithOnlyNullItems = {name: 'John', nicknames: [null, undefined], age: 37} as unknown as Filter;
+const filterWithEmptyArray: Filter = {name: 'John', nicknames: [], age: 37};
 const country: string = "Belgium";
 const tags: Set<string> = new Set(['a', 'b']);
 
@@ -75,6 +80,13 @@ describe('Form Query Param testing', () => {
     expect(req.request.method).toEqual('GET');
   });
 
+  it('should separate the query parameter with ampersands (object with undefined field)', async () => {
+    service.searchExplode(undefined, filterWithUndefined, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_explode?name=John&nicknames=Joe');
+    expect(req.request.method).toEqual('GET');
+  });
+
   it('should separate the query parameter with ampersands (simple only)', async () => {
     service.searchExplode(undefined, undefined, country).subscribe();
     const req = httpTesting.expectOne('http://localhost/search_explode?country=Belgium');
@@ -133,6 +145,41 @@ describe('Form Query Param testing', () => {
     expect(req.request.method).toEqual('GET');
   });
 
+  it('should separate the query parameter with comma (object with undefined field)', async () => {
+    service.searchNotExplode(undefined, filterWithUndefined, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_not_explode?filter=name,John,nicknames,Joe');
+    expect(req.request.method).toEqual('GET');
+  });
+
+  it('should separate the query parameter with comma (object with all fields undefined)', async () => {
+    service.searchNotExplode(undefined, filterAllUndefined, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_not_explode?filter=');
+    expect(req.request.method).toEqual('GET');
+  });
+
+  it('should separate the query parameter with comma (object with null array items)', async () => {
+    service.searchNotExplode(undefined, filterWithNullItems, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_not_explode?filter=name,John,nicknames,Joe');
+    expect(req.request.method).toEqual('GET');
+  });
+
+  it('should separate the query parameter with comma (object with only null array items)', async () => {
+    service.searchNotExplode(undefined, filterWithOnlyNullItems, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_not_explode?filter=name,John,age,37');
+    expect(req.request.method).toEqual('GET');
+  });
+
+  it('should separate the query parameter with comma (object with empty array field)', async () => {
+    service.searchNotExplode(undefined, filterWithEmptyArray, undefined).subscribe();
+
+    const req = httpTesting.expectOne('http://localhost/search_not_explode?filter=name,John,age,37');
+    expect(req.request.method).toEqual('GET');
+  });
+
   it('should separate the query parameter with comma (simple only)', async () => {
     service.searchNotExplode(undefined, undefined, country).subscribe();
     const req = httpTesting.expectOne('http://localhost/search_not_explode?country=Belgium');
diff --git a/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/query.params.ts b/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/query.params.ts
+++ b/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/others/typescript-angular/builds/composed-schemas/query.params.ts b/samples/client/others/typescript-angular/builds/composed-schemas/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/others/typescript-angular/builds/composed-schemas/query.params.ts
+++ b/samples/client/others/typescript-angular/builds/composed-schemas/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v19/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v19/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v19/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v19/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v20/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v20/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v20/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v20/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v21/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v21/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v21/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v21/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/query.params.ts b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }
 
diff --git a/samples/client/petstore/typescript-angular-v22/builds/default/query.params.ts b/samples/client/petstore/typescript-angular-v22/builds/default/query.params.ts
index 4076c1140c83..978fde0d2ea2 100644
--- a/samples/client/petstore/typescript-angular-v22/builds/default/query.params.ts
+++ b/samples/client/petstore/typescript-angular-v22/builds/default/query.params.ts
@@ -137,14 +137,20 @@ export function concatHttpParamsObject(httpParams: OpenApiHttpParams, key: strin
     let keyAndValues: string[] = [];
 
     for (const k in item) {
-        keyAndValues.push(k);
-
         const value = item[k];
 
+        if (value === null || value === undefined) {
+            continue;
+        }
+
         if (Array.isArray(value)) {
-            keyAndValues.push(...value.map(convertToString));
+            const items = value.filter(v => v !== null && v !== undefined);
+
+            if (items.length > 0) {
+                keyAndValues.push(k, ...items.map(convertToString));
+            }
         } else {
-            keyAndValues.push(convertToString(value));
+            keyAndValues.push(k, convertToString(value));
         }
     }