"Federal Trademark Litigation vs. Trademark Trial and Appeal Board Practice: Differences That Matter"
Below is an excerpt:
The most significant difference between federal court litigation and TTAB proceedings is that the TTAB does not hear live testimony.
Instead, the party offering witness testimony generally must take that testimony as a deposition held during each party’s 30-day trial period.
However, pursuant to 37 C.F.R. § 2.123(b), if the parties so stipulate in writing, the testimony of any witness may be submitted in the form of an affidavit or declaration.