NOTICE file missing

[Yann Hamon]

The source code mentions a contributor license agreement:

ssllabs-scan/ssllabs-scan-v3.go

Lines 4 to 6 in 7a9f44e

  * Licensed to Qualys, Inc. (QUALYS) under one or more 
  * contributor license agreements. See the NOTICE file distributed with 
  * this work for additional information regarding copyright ownership. 

Especially "See the NOTICE file distributed with this work for additional information regarding copyright ownership."

Does contributing to this software require agreeing to a contributor license agreement? Would this requirement also apply to forks?

Many thanks!