(Bloomberg) Accenture Ltd., the world?s second- largest consultant, thought it won an exemption in Congress last year from penalties on US companies that have moved to overseas jurisdictions with little or no taxation.

Now the company is trying to make sure the US?s federal taxation bureau, the Internal Revenue Service agrees. Accenture is lobbying the US Congress to make a so-called technical correction to the law to prevent any challenge from the tax collector.

Aides to New York Congressman Charles Rangel, the top Democrat on the House Ways and Means Committee, say they are objecting to the proposed fix, complicating a process that usually requires the consensus of top congressional tax-writers, their aides, US Treasury officials, and the congress? Joint Committee on Taxation.

Democrats, who won a ban on Accenture and other companies that have established legal addresses abroad such as Tyco International Ltd. and Ingersoll-Rand Ltd. from bidding on government contracts, may use the squabble as an opportunity to raise new objections.

?We?ve had this argument for the last four or five years,? said Richard Neal, a Massachusetts Democrat who serves on the Ways and Means Committee and has criticised Accenture?s incorporation in Bermuda as a tax dodge. The technical correction amounts to ?picking a winner,? Neal said.

A provision in last year?s $145 billion corporate tax bill would treat companies that move to low taxation Bermuda and or to tax haven countries as US-based for tax purposes, denying them tax breaks.

The law exempts companies that completed a move prior to March 4, 2003. According to the firm, it is concerned the IRS might argue it isn?t grandfathered along with Tyco and Ingersoll-Rand because of the way it formalised its Bermuda incorporation.

Without a wording change in the law, Accenture says it risks a battle with the IRS, even though Accenture said Congress intended for the firm to be grandfathered. Accenture said in regulatory filings that it doesn?t believe the provision maintaining US corporate taxes on companies that move to tax havens applies to Accenture.

?However, we are not able to predict with certainty whether the US Internal Revenue Service will challenge our interpretation of the legislation,? the company said. ?Nor are we able to predict with certainty the impact of regulations or other interpretations that might be issued related to this legislation. It is possible that certain interpretations could materially increase our tax burden.?

Accenture Spokeswoman Roxanne Taylor declined to comment on the company?s lobbying efforts. The firm?s lobbyists, Jon Talisman and Rick Grafmeyer of Capitol Tax Partners, declined to comment for the record. The IRS by law can?t comment on specific taxpayers.

Accenture split from accounting firm Arthur Andersen LLP in 2000 and established its legal address in Bermuda a year later. It also established a complicated network of business entities in Switzerland and Luxembourg that allowed the company to take advantage of myriad tax treaties with the US that reduce or exempt income from intellectual property and finance operations.

The company?s US tax bill has declined at the same time its income from US sources has increased, according to its filings. Accenture earned $503 million in the US in 2004, up from $247.3 million in 2002. Since 2002, the company has reduced its US tax liability to $135.5 million from $241.27 million.

Outside the US, Accenture earned $1.3 billion in 2004, up from $820.3 million in 2002. It paid $318.8 million in taxes to foreign governments in 2004 compared with $358 million in 2002.