diff --git a/package.json b/package.json
index a20594eafa..8b43950bbd 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
         "@types/hammerjs": "2.0.35",
         "@types/jasmine": "~3.3.13",
         "@types/node": "10.12.20",
+        "@types/semver": "6.2.0",
         "bazel_workspaces": "file:./tools/npm_packages/bazel_workspaces",
         "clang-format": "1.2.2",
         "conventional-changelog-cli": "^2.0.21",
diff --git a/packages/typescript/test/strict_deps/BUILD b/packages/typescript/test/strict_deps/BUILD
index 6db23abc05..eaaf04402f 100644
--- a/packages/typescript/test/strict_deps/BUILD
+++ b/packages/typescript/test/strict_deps/BUILD
@@ -22,7 +22,17 @@ ts_library(
 ts_library(
     name = "parent",
     srcs = ["parent.ts"],
-    deps = [":grandparent"],
+    # NB: We don't require the `@npm//semver` package for the typescript compile
+    # action as the .d.ts files live in @types/semver. If the resulting
+    # .js file is run downstream in a nodejs_binary rule, however, the
+    # `@npm//semver` dep will be required at that point.
+    # TODO: Is it desirable to automatically add @npm//semver as a transitive
+    #       dep if @npm//@types/semver is a dep so that downtream nodejs_binary
+    #       rules get this automatically?
+    deps = [
+        ":grandparent",
+        "@npm//@types/semver",
+    ],
 )
 
 ts_library(
@@ -33,3 +43,12 @@ ts_library(
     ],
     deps = [":parent"],
 )
+
+ts_library(
+    name = "strict_deps_npm",
+    srcs = ["child2.ts"],
+    expected_diagnostics = [
+        "TS2307:child2\.ts\(2,.*transitive dependency.*not allowed",
+    ],
+    deps = [":parent"],
+)
diff --git a/packages/typescript/test/strict_deps/child.ts b/packages/typescript/test/strict_deps/child.ts
index f7bca1371a..f0ba5d9e6a 100644
--- a/packages/typescript/test/strict_deps/child.ts
+++ b/packages/typescript/test/strict_deps/child.ts
@@ -1,4 +1,4 @@
-// The line below is a strict deps violation:
+// The line below is a strict deps violation of a ts_library dep
 import {Symbol} from './grandparent';
 
 console.log(Symbol);
diff --git a/packages/typescript/test/strict_deps/child2.ts b/packages/typescript/test/strict_deps/child2.ts
new file mode 100644
index 0000000000..b2ced6b602
--- /dev/null
+++ b/packages/typescript/test/strict_deps/child2.ts
@@ -0,0 +1,5 @@
+// The line below is a strict deps violation of an @npm dep
+import * as semver from 'semver';
+semver.valid('1.2.3');
+
+console.log(Symbol);
diff --git a/packages/typescript/test/strict_deps/parent.ts b/packages/typescript/test/strict_deps/parent.ts
index 6df328773d..cffa1013a1 100644
--- a/packages/typescript/test/strict_deps/parent.ts
+++ b/packages/typescript/test/strict_deps/parent.ts
@@ -1,4 +1,5 @@
+import * as semver from 'semver';
 import {Symbol} from './grandparent';
+semver.valid('1.2.3');
 export const x = 1;
-
 console.log(Symbol);
diff --git a/yarn.lock b/yarn.lock
index b6821b142b..b476728990 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1050,6 +1050,11 @@
   resolved "https://registry.yarnpkg.com/@types/selenium-webdriver/-/selenium-webdriver-3.0.16.tgz#50a4755f8e33edacd9c406729e9b930d2451902a"
   integrity sha512-lMC2G0ItF2xv4UCiwbJGbnJlIuUixHrioOhNGHSCsYCJ8l4t9hMCUimCytvFv7qy6AfSzRxhRHoGa+UqaqwyeA==
 
+"@types/semver@6.2.0":
+  version "6.2.0"
+  resolved "https://registry.yarnpkg.com/@types/semver/-/semver-6.2.0.tgz#d688d574400d96c5b0114968705366f431831e1a"
+  integrity sha512-1OzrNb4RuAzIT7wHSsgZRlMBlNsJl+do6UblR7JMW4oB7bbR+uBEYtUh7gEc/jM84GGilh68lSOokyM/zNUlBA==
+
 "@types/semver@^6.0.1":
   version "6.0.1"
   resolved "https://registry.yarnpkg.com/@types/semver/-/semver-6.0.1.tgz#a984b405c702fa5a7ec6abc56b37f2ba35ef5af6"