SAN FRANCISCO — Apple is being fined US$25,000 per day for missing a court-imposed deadline to produce evidence in a government lawsuit that alleges mobile chip supplier Qualcomm has been imposing unfair licensing terms on the makers of smartphones.

The fine imposed Thursday by a federal magistrate judge in San Jose, California, is retroactive to Dec. 16 and will remain in effect until Dec. 29. If Apple hasn't produced all 1.3 million documents covered by an order issued in October, U.S. Magistrate Judge Nathanael Cousins intends to increase the fine.

In a statement, Apple (AAPL.O) said it plans to appeal Cousins' ruling in a case pitting the Federal Trade Commission against Qualcomm, whose technology is used in most of the world's smartphones.

"We have already produced millions of documents for this case and are working hard to deliver the millions more which have been requested in an unprecedented timeframe," said Apple, which is based in Cupertino, California.

San Diego-based Qualcomm Inc. (QCOM.O) declined comment.

Although it isn't directly involved in the FTC's suit against Qualcomm, Apple has been co-operating with the U.S. government in its investigation. Qualcomm is seeking Apple's documents as part of its effort to prove the FTC's allegations are wrong.

As the maker of the iPhone, Apple also has an axe to grind against Qualcomm. Apple sued Qualcomm in a different lawsuit shortly after the FTC lodged its complaint. Apple is accusing Qualcomm of abusing its power to extort royalties from iPhone innovations that have nothing to do with its technology. Qualcomm has denied those allegations and is countersuing Apple, raising the rancour between the two companies.

Even if Apple is fined the maximum amount of US$350,000 through Dec. 29 under the court ruling, it will barely faze a company that has about US$270 billion in cash.