Sept. 21 (Bloomberg) -- Dell Inc.’s $3.9 billion offer for computer-services provider Perot Systems Corp. stands to make the Perot family almost $400 million richer, according to company filings.

Almost 25 percent of Plano, Texas-based Perot Systems belongs to HWGA Ltd., which is the family’s investment company. Founder Ross Perot Sr. is HWGA’s managing partner. An additional 2.08 million shares, or 1.7 percent of Perot Systems, belonged to Perot family trusts as of March 16, filings show.

The two blocks of stock together are valued at $952 million at the $30-a-share acquisition price, which is 68 percent more than the family’s $568 million stake on Sept. 18, before the deal was announced. Ross Perot Sr. has an estimated worth of about $5 billion and his son, chairman Ross Perot Jr., has a fortune of about $2.2 billion, according to Forbes magazine.

The elder Perot, 79, founded computer-services company Electronic Data Systems Corp. in 1962. He sold control of the company to General Motors Corp. in 1984. Dissatisfied with how GM ran his old company, he quit GM’s board and founded Perot Systems in 1988. EDS now belongs to Hewlett-Packard Co., which paid $13.2 billion for the company last year.

Perot Systems jumped $11.65, or 65 percent, to $29.56 at 4 p.m. in New York Stock Exchange composite trading. The shares have more than doubled this year. Dell fell 68 cents, or 4.1 percent, to $16.01 on the Nasdaq Stock Market.

Father and Son

Perot Sr. ran for U.S. President in 1992 and 1996, each time touting his business acumen as a qualification. He pledged to balance the federal budget, and compared politicians’ ignoring the federal deficit to families hiding a “crazy aunt” from the neighbors. He tied for 68th place on Forbes’s list of the 400 Richest Americans last year.

Perot Jr., 50, owned the Dallas Mavericks basketball team, which he sold to Mark Cuban in 2000, after making his early mark as a real-estate developer in Dallas. He made the Forbes 400 list for first time last year, ranking 205th, after he and his father sold off natural gas interests in Texas while keeping the right to build on the property, the magazine said.

The younger Perot also has the right to acquire an additional 1.58 million Perot Systems shares, valued at $47.4 million at the offer price, upon the exercise of vested stock options, according to company filings.

Last Updated: September 21, 2009 16:27 EDT