Christopher J. Steskal, a lead prosecutor of a federal task force investigating the backdating of stock options at Apple Inc. and other companies, is leaving his San Francisco post to join a law firm, the United State Attorney’s office in San Francisco confirmed late Friday.

Mr. Steskal’s decision follows the recent resignation of his boss, United States Attorney Kevin V. Ryan.

Mr. Steskal also was the lead prosecutor in the government’s case against Gregory L. Reyes, the former chief executive of Brocade Communications Systems.

Mr. Steskal, who was to try Mr. Reyes’s case in June in San Francisco, is the second of five assistant United States attorneys on the task force to leave since its formation in July. He said he would join the San Francisco office of Fenwick & West within 30 days.

William J. Portanova, a criminal defense attorney and former federal prosecutor, said that he believed that the Brocade case would not suffer, no matter who is picked to succeed Mr. Steskal.

“The government has people stacked up ready to pick up the case and run with it,” he said.

Luke Macaulay, a spokesman for the United States Attorney’s office in San Francisco, said that one of two prosecutors the office is planning to hire would replace Mr. Steskal on the task force.

An Iraqi cabinet-level committee proposed a draft law Friday that would allow the national government in Iraq to control oil revenues. Negotiations concerning the draft law have been a source of tension in Iraq for months as most Kurds and many Shiites want to retain control of the country's oil resources. On the other hand, Sunni Arabs, who do not dominate the oil-rich regions of the country, insist on central oversight.

Recent debate has centered on the establishment of a federal committee, called the Federal Oil and Gas Council, to review oil contracts. Kurds did not want to give the committee the power to "approve" contracts, so the draft law instead allows regions to initiate and guide the process of awarding oil contracts and gives the committee the power to review and reject contracts. The Iraqi cabinet and the country's parliament must approve the draft before it becomes law. If the draft passes, enforcement might prove difficult in Iraq's wartime environment.

Mexico extradited drug kingpins Osiel Cardenas and Hector "El Guero" Palma and thirteen other major traffickers to the United States Friday as part of an effort by new Mexican president Felipe Calderon to follow through on a promise made by former President Vincente Fox to make increased extraditions to the US. Since taking office, Calderon has mobilized elite police and military forces against the rival Sinaloa and Gulf Cartels. Although the widely popular initiative is showing initial success, experts warn that Calderon must address the political and judicial corruption that allows cartels to run rampant in Mexico.

Kingpins are often able to continue running their organizations from within corrupt Mexican prisons, making the extradition of leaders a key tool for scaling back cartel activity. In November 2005, the Supreme Court of Mexico ruled that prisoners serving life sentences can be extradited abroad, overturning a 2001 decision that prevented such prisoners from answering to charges in the US insofar as punishment there might be cruel and unusual and not directed at rehabilitation of the prisoner. A 1978 treaty between the US and Mexico still prevents the extradition of prisoners who face the death penalty.

Issue ads are those that do not purport to influence an election, but rather focus attention on an issue their sponsors find important. A provision of the McCain-Feingold law prohibits mentioning a candidate in issue ads in the 60 days before a general election and 30 days before a primary.

Its purpose was to end the common practice of circumventing limits on contributions in federal elections by airing ads that avoided expressly advocating a vote for or against someone while making clear a preference for, or more often, disapproval of one candidate.

A lawsuit in which record companies allege XM Satellite Radio Holdings Inc. is cheating them by letting consumers store songs can proceed toward trial, a judge ruled Friday after finding merit to the companies' claims.

U.S. District Judge Deborah A. Batts made the finding in a case brought by Atlantic Recording Corp., BMG Music, Capitol Records Inc. and other music distribution companies against the licensed satellite radio broadcaster.

In a lawsuit last year, the companies said XM directly infringes on their exclusive distribution rights by letting consumers record songs onto special receivers marketed as "XM + MP3" players.

XM has argued it is protected from infringement lawsuits by the Audio Home Recording Act of 1992, which permits individuals to record music off the radio for private use. The judge said she did not believe the company was protected in this instance by the act.

In a statement, XM said it remains confident that the lawsuit is without merit and it will prevail.

"At this stage of the proceeding, the court's ruling is required to be based on the false characterizations set forth in the plaintiffs' complaint. The real facts strongly support our view that the lawsuit is barred by the Audio Home Recording Act. We look forward to making our case in court," the company said.

Messages for comment left with lawyers on both sides were not immediately returned.

In refusing to toss out the lawsuit, the judge noted that the record companies consent to XM's use of their copyrighted material solely for the purposes of providing a digital satellite broadcasting service.

She said XM operates like traditional radio broadcast providers who cannot offer an interactive service, publish programming schedules prior to broadcast and play songs from an artist more often than specified within a three-hour period. But by broadcasting and storing copyrighted music for later recording by the consumer, the judge said XM is both a broadcaster and a distributor, but only paying to be a broadcaster.

"The record companies sufficiently allege that serving as a music distributor to XM + MP3 users gives XM added commercial benefit as a satellite radio broadcaster," Batts said.

Although XM argued in court papers that an XM + MP3 player is much like a traditional radio-cassette player, the judge said "it is not."

"It is manifestly apparent that the use of a radio-cassette player to record songs played over free radio does not threaten the market for copyrighted works as does the use of a recorder which stores songs from private radio broadcasts on a subscription fee basis," she said.

XM shares fell 70 cents, or 4.3 percent, to $15.75 in midday trading on the Nasdaq Stock Market.