Prevent Unity stripping GPU instancing shaders in the Built-In Render Pipeline

Important: The Built-In Render Pipeline is deprecated and will be made obsolete in a future release.
It remains supported, including bug fixes and maintenance, through the full Unity 6.7 LTS lifecycle.
For more information on migration, refer to Migrating from the Built-In Render Pipeline to the Universal Render Pipeline and Render pipeline feature comparison.

Unity generates Surface shaders with instancing variants by default, unless you specify noinstancing in the #pragma directive. Unity ignores uses of #pragma multi_compile_instancing in a surface shader.

Unity’s Standard and StandardSpecular shaders have instancing support by default, but with no per-instance properties other than the transform.

If your scene contains no GameObjects with GPU instancing enabled, then Unity strips instancing shader variants. To override the stripping behaviour:

Open Project Settings (menu: Edit > Project Settings).
Go to Graphics.
In the Shader Stripping section, set Instancing Variants to Keep All.

Example of changing per-instance data at runtime in the Built-In Render Pipeline

GPU instancing shader reference for the Built-In Render Pipeline

Unity Manual

Prevent Unity stripping GPU instancing shaders in the Built-In Render Pipeline