/usr/lib/pkgconfig/system.web.mvc3.pc is in libmono-cil-dev 3.2.8+dfsg-10.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 | Name: System.Web.Mvc3
Description: System.Web.Mvc - ASP.NET MVC v3
Version: 3.0.0.0
Libs: -r:/usr/lib/mono/gac/System.Web.Mvc/3.0.0.0__31bf3856ad364e35/System.Web.Mvc.dll
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