A couple of decades ago, in the commentary track for the OOP Criterion Collection edition of "This Spinal Tap", Shearer discussed how he, McKeon and Guest had to negotiate an agreement in order to portray the characters they created.
Quote:
"Shearer's company says that in 2013, in anticipation of the film's 30th anniversary, it commissioned a study of accounting statements and revenue streams and 'then first discovered that Vivendi had engaged in a pattern of anti-competitive and unfair business practices, had abandoned enforcement of valuable TIST rights, and had willfully concealed and manipulated years of accountings to retain monies due and owing to Plaintiff.'
http://www.hollywoodreporter.com/thr-es ... ion-939205