The U.S. Supreme Court set off a patent law earthquake with its venue decision TC Heartland v. Kraft Foods Group Brands. But three months later it's still unclear how far the shock waves will spread.

An analysis of litigation since the high court's May 22 decision shows district judges, tech companies and patent owners jockeying over the decision's reach with early rulings setting a bar for establishing venue that may be relatively easy to meet, at least in suits against big companies. Still the immediate impact on patent filings has been pronounced in anticipated—and some unanticipated—ways.

More than 350 motions to transfer or dismiss cases have been filed in the U.S. District Court for the Eastern District of Texas alone, according to data compiled by defensive patent aggregator RPX Corp. But there's a deepening difference of opinion among district judges on whether defendants who have already dug into litigation waived their right to invoke the new law.