diff --git a/package-lock.json b/package-lock.json
index f43fe71308..54b4f6158f 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -103,8 +103,7 @@
         "semver": "7.5.4",
         "sinon": "15.2.0",
         "sinon-chai": "3.7.0",
-        "square-calc": "3.2.1",
-        "square-calc-v2": "npm:square-calc@2.4.0",
+        "square-calc": "3.3.1",
         "stealthy-require": "1.1.1",
         "typescript": "5.9.3",
         "underscore": "1.13.1",
@@ -31195,17 +31194,11 @@
       "dev": true
     },
     "node_modules/square-calc": {
-      "version": "3.2.1",
-      "resolved": "https://registry.npmjs.org/square-calc/-/square-calc-3.2.1.tgz",
-      "integrity": "sha512-43TtHbgIdE5V9hPsIMRPXFcxQvP0QXZ2MjoI/xak3YiIJ4GMsdhFwXnShM3CCcIovaOd35KzF+xxQX0urACHqw==",
-      "dev": true
-    },
-    "node_modules/square-calc-v2": {
-      "name": "square-calc",
-      "version": "2.4.0",
-      "resolved": "https://registry.npmjs.org/square-calc/-/square-calc-2.4.0.tgz",
-      "integrity": "sha512-9ud3FeFngJmIpEsiep4lvNhw1NvKLtirowvaMomMeHjyzJckDRbSbLkFv3Jjae6j+ZtxTd2eJvO8izkdpGCDDA==",
-      "dev": true
+      "version": "3.3.1",
+      "resolved": "https://registry.npmjs.org/square-calc/-/square-calc-3.3.1.tgz",
+      "integrity": "sha512-x329+gUanrlP77wqRv3ckVG/KP6MEg6xrPfr6tAeKLvxX+cv6tXbURgeV7CevzrsKpjV9FvG9FPljqBbED7DEw==",
+      "dev": true,
+      "license": "MIT"
     },
     "node_modules/ssri": {
       "version": "12.0.0",
diff --git a/package.json b/package.json
index aa0f6f0b34..90329bc600 100644
--- a/package.json
+++ b/package.json
@@ -160,8 +160,7 @@
     "semver": "7.5.4",
     "sinon": "15.2.0",
     "sinon-chai": "3.7.0",
-    "square-calc": "3.2.1",
-    "square-calc-v2": "npm:square-calc@2.4.0",
+    "square-calc": "3.3.1",
     "stealthy-require": "1.1.1",
     "typescript": "5.9.3",
     "underscore": "1.13.1",
diff --git a/packages/collector/test/integration/misc/native_esm/app.js b/packages/collector/test/integration/misc/native_esm/app.js
index 7b89fddee4..0ba6db94b5 100644
--- a/packages/collector/test/integration/misc/native_esm/app.js
+++ b/packages/collector/test/integration/misc/native_esm/app.js
@@ -10,8 +10,6 @@ process.on('SIGTERM', () => {
   process.exit(0);
 });
 
-const mock = require('@_local/core/test/test_util/mockRequire');
-mock('square-calc', 'square-calc-v2');
 require('@instana/collector')();
 const express = require('express');
 const morgan = require('morgan');
diff --git a/packages/collector/test/tracing/misc/require-esm/app.js b/packages/collector/test/tracing/misc/require-esm/app.js
new file mode 100644
index 0000000000..dfd1d2335d
--- /dev/null
+++ b/packages/collector/test/tracing/misc/require-esm/app.js
@@ -0,0 +1,63 @@
+/*
+ * (c) Copyright IBM Corp. 2026
+ */
+
+'use strict';
+
+// NOTE: c8 bug https://github.com/bcoe/c8/issues/166
+process.on('SIGTERM', () => {
+  process.disconnect();
+  process.exit(0);
+});
+
+const agentPort = process.env.INSTANA_AGENT_PORT;
+
+require('@instana/collector')();
+
+// Load ESM-only dependency using Node.js native require(esm) support
+// 'got' is pure ESM from v14+. Since require(esm) returns the full Module Namespace Object
+// rather than an unwrapped default function, we must explicitly destructure `.default`.
+const { default: got } = require('got');
+
+const express = require('express');
+const port = require('@_local/collector/test/test_util/app-port')();
+const app = express();
+const logPrefix = `require(esm) test app (${process.pid}):\t`;
+
+function log() {
+  const args = Array.prototype.slice.call(arguments);
+  args[0] = `${logPrefix}${args[0]}`;
+  // eslint-disable-next-line no-console
+  console.log.apply(console, args);
+}
+
+app.get('/', (req, res) => {
+  res.send('OK');
+});
+
+app.get('/make-request', async (req, res) => {
+  const targetUrl = `http://127.0.0.1:${agentPort}/`;
+
+  try {
+    const response = await got(targetUrl);
+
+    log(`Request successful, status: ${response.statusCode}`);
+    res.json({
+      success: true,
+      statusCode: response.statusCode,
+      url: targetUrl,
+      bodyLength: response.body.length
+    });
+  } catch (error) {
+    log(`Request failed: ${error.message}`);
+    res.status(500).json({
+      success: false,
+      error: error.message,
+      url: targetUrl
+    });
+  }
+});
+
+app.listen(port, () => {
+  log(`Listening on port: ${port}`);
+});
diff --git a/packages/collector/test/tracing/misc/require-esm/package.json b/packages/collector/test/tracing/misc/require-esm/package.json
new file mode 100644
index 0000000000..a902b9e131
--- /dev/null
+++ b/packages/collector/test/tracing/misc/require-esm/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "require-esm-test",
+  "version": "1.0.0",
+  "description": "Test for Node.js require(esm) support",
+  "main": "app.js",
+  "dependencies": {
+    "got": "latest"
+  }
+}
diff --git a/packages/collector/test/tracing/misc/require-esm/test.js b/packages/collector/test/tracing/misc/require-esm/test.js
new file mode 100644
index 0000000000..bca0b0680e
--- /dev/null
+++ b/packages/collector/test/tracing/misc/require-esm/test.js
@@ -0,0 +1,13 @@
+/*
+ * (c) Copyright IBM Corp. 2026
+ */
+
+'use strict';
+
+const config = require('@instana/core/test/config');
+
+describe('tracing/misc/require-esm', function () {
+  this.timeout(config.getTestTimeout() * 2);
+
+  require('./test_base')();
+});
diff --git a/packages/collector/test/tracing/misc/require-esm/test_base.js b/packages/collector/test/tracing/misc/require-esm/test_base.js
new file mode 100644
index 0000000000..8d44266356
--- /dev/null
+++ b/packages/collector/test/tracing/misc/require-esm/test_base.js
@@ -0,0 +1,124 @@
+/*
+ * (c) Copyright IBM Corp. 2026
+ */
+
+'use strict';
+
+const semver = require('semver');
+const expect = require('chai').expect;
+const { supportedVersion } = require('@instana/core').tracing;
+const config = require('@instana/core/test/config');
+const { retry, expectExactlyOneMatching } = require('@instana/core/test/test_util');
+const ProcessControls = require('@instana/collector/test/test_util/ProcessControls');
+const globalAgent = require('@instana/collector/test/globalAgent');
+
+const supportsRequireESM = semver.gte(process.versions.node, '20.19.0');
+const mochaSuiteFn = supportedVersion(process.versions.node) && supportsRequireESM ? describe : describe.skip;
+
+module.exports = function () {
+  mochaSuiteFn('tracing/require(esm)', function () {
+    this.timeout(config.getTestTimeout() * 2);
+
+    globalAgent.setUpCleanUpHooks();
+    const agentControls = globalAgent.instance;
+
+    describe('tracing enabled, no suppression', function () {
+      let controls;
+
+      before(async () => {
+        controls = new ProcessControls({
+          dirname: __dirname,
+          useGlobalAgent: true
+        });
+
+        await controls.startAndWaitForAgentConnection();
+      });
+
+      beforeEach(async () => {
+        await agentControls.clearReceivedTraceData();
+      });
+
+      after(async () => {
+        await controls.stop();
+      });
+
+      afterEach(async () => {
+        await controls.clearIpcMessages();
+      });
+
+      it('must trace HTTP requests made with ESM-only package loaded via require()', async () => {
+        const response = await controls.sendRequest({
+          method: 'GET',
+          path: '/make-request'
+        });
+
+        expect(response.success).to.equal(true);
+        expect(response.statusCode).to.equal(200);
+
+        await retry(async () => {
+          const spans = await agentControls.getSpans();
+
+          expect(spans).to.have.lengthOf(2);
+
+          const httpEntry = expectExactlyOneMatching(spans, [
+            span => expect(span.n).to.equal('node.http.server'),
+            span => expect(span.k).to.equal(1),
+            span => expect(span.data.http.method).to.equal('GET'),
+            span => expect(span.data.http.url).to.match(/\/make-request/)
+          ]);
+
+          const httpExit = expectExactlyOneMatching(spans, [
+            span => expect(span.n).to.equal('node.http.client'),
+            span => expect(span.k).to.equal(2),
+            span => expect(span.t).to.equal(httpEntry.t),
+            span => expect(span.p).to.equal(httpEntry.s),
+            span => expect(span.data.http.method).to.equal('GET'),
+            span => expect(span.data.http.url).to.include('127.0.0.1')
+          ]);
+
+          expect(httpExit.data.http.status).to.equal(200);
+          expect(httpExit.ec).to.equal(0);
+          expect(httpEntry.ec).to.equal(0);
+        });
+      });
+    });
+
+    describe('tracing suppressed', function () {
+      let controls;
+
+      before(async () => {
+        controls = new ProcessControls({
+          dirname: __dirname,
+          useGlobalAgent: true
+        });
+
+        await controls.startAndWaitForAgentConnection();
+      });
+
+      beforeEach(async () => {
+        await agentControls.clearReceivedTraceData();
+      });
+
+      after(async () => {
+        await controls.stop();
+      });
+
+      afterEach(async () => {
+        await controls.clearIpcMessages();
+      });
+
+      it('should not trace when suppressed', async () => {
+        await controls.sendRequest({
+          method: 'GET',
+          path: '/make-request',
+          suppressTracing: true
+        });
+
+        await retry(async () => {
+          const spans = await agentControls.getSpans();
+          expect(spans).to.have.lengthOf(0);
+        });
+      });
+    });
+  });
+};