The Supreme Court has laid out the elements for the federal crime of perjury under 18 U.S.C. § 1621 as follows:
‘The essential elements of the crime of perjury as defined in 18 U.S.C. s 1621, 18 U.S.C.A. s 1621, are (1) an oath authorized by a law of the United States, (2) taken before a competent tribunal, officer or person, and (3) a false statement wilfully made as to facts material to the hearing.’ United States v. Debrow, 346 U.S. 374, 376, 74 S.Ct. 113, 115, 98 L.Ed. 92.
United States v. Hvass, 355 U.S. 570, 574, 78 S. Ct. 501, 504, 2 L. Ed. 2d 496 (1958). In general deposition testimony taken for a case being litigated in federal court will meet (1) and (2). The problem with most perjury prosecutions is proving (3), that the defendant willfully made a false statement of a material fact. Proving that the defendant knew the statement was false and made the false statement willfully rather than making a mistake, having poor memory, or whatever, is especially difficult. This is why you don't see all that many perjury prosecutions.
In any event, if you think perjury was committed, you are free to report the matter to the FBI. You don't have to be an expert on perjury to do that. The FBI and U.S. attorney will decide if there is evidence sufficient enough to pursue a perjury prosecution and whether they want to devote the resources to doing it. After all, you don't prosecute the perjury; the U.S. Attorney does.