Ford Motor Co. on Friday announced new steps aimed at protecting $19 billion in company tax benefits.

U.S. tax laws allow companies to defer the tax benefits of operating losses, capital losses and tax credits to offset future profits. However, those benefits go away if there is a substantial change in a company's ownership.

The move does not affect most shareholders.

The rules were established to keep profitable companies from buying out unprofitable firms solely to take advantage of their tax benefits.

Ford, which has not posted a full-year profit since 2005, has accumulated some $19 billion in such tax benefits.

Now, the Dearborn automaker is concerned that recent moves to trade debt for equity and use company stock to cover part of its obligation to a union-run retiree health care trust fund -- known as a Voluntary Employees' Beneficiary Association, or VEBA -- could unintentionally result in a technical change in ownership under these rules.

To prevent that from happening, Ford's board of directors voted Wednesday to give each shareholder of record as of Sept. 25 the right to buy one share of preferred stock for each share of common or Class B stock they own if a holder of 5 percent or more of Ford stock increases their ownership stake by more than half a percentage point or a new stockholder acquires more than 4.99 percent of Ford's shares.

That action would dilute the large shareholder that triggered the action and protect Ford's tax benefits.

"This plan is designed to protect shareholder value and safeguard valuable tax attributes by reducing the likelihood of an unintended 'ownership change' through actions involving Ford common stock," said Lewis Booth, Ford's chief financial officer.

The prospect of a hostile takeover has never been a real threat to Ford, which is controlled by the Ford family through its exclusive control of the company's super-voting Class B shares.

Ford spokesman Mark Truby said that more than 30 other major corporations have enacted similar stock provisions this year and said Ford's actions are primarily intended to prevent major institutional investors from inadvertently crossing the IRS threshold.

"This is strictly to protect valuable tax assets and is not intended as an anti-takeover measure," he said.

"It doesn't have any impact on our normal shareholders."