That one got me really confused because different people would get different behaviors, and behavior will vary with time on same machine, and repro would go away every time we pushed a new version of the package.
To repro: have a package with multiple owners.
Simplified repro from server vs. from cache..
F:\tmp\NugetBug>del %LOCALAPPDATA%\nuget\cache\*.*
AppData\Local\nuget\cache\*.*, Are you sure (Y/N)? y
F:\tmp\NugetBug>nuget install test -source http://localhost -outputdirectory first -saveonexpand nuspec
Installing 'test 3.0.55.2'.
Successfully installed 'test 3.0.55.2'.
F:\tmp\NugetBug>findstr owners first\test.3.0.55.2\test.3.0.55.2.nuspec
<owners>owner</owners>
F:\tmp\NugetBug>nuget install test-source http://localhost -outputdirectory second -saveonexpand nuspec
Installing 'test 3.0.55.2'.
Successfully installed 'test 3.0.55.2'.
F:\tmp\NugetBug>findstr owners second\test.3.0.55.2\test.3.0.55.2.nuspec
<owners>test,companyname</owners>
To repro: have a package with multiple owners.
Simplified repro from server vs. from cache..
F:\tmp\NugetBug>del %LOCALAPPDATA%\nuget\cache\*.*
AppData\Local\nuget\cache\*.*, Are you sure (Y/N)? y
F:\tmp\NugetBug>nuget install test -source http://localhost -outputdirectory first -saveonexpand nuspec
Installing 'test 3.0.55.2'.
Successfully installed 'test 3.0.55.2'.
F:\tmp\NugetBug>findstr owners first\test.3.0.55.2\test.3.0.55.2.nuspec
<owners>owner</owners>
F:\tmp\NugetBug>nuget install test-source http://localhost -outputdirectory second -saveonexpand nuspec
Installing 'test 3.0.55.2'.
Successfully installed 'test 3.0.55.2'.
F:\tmp\NugetBug>findstr owners second\test.3.0.55.2\test.3.0.55.2.nuspec
<owners>test,companyname</owners>