Dell Inc.’s five-year-old campaign to transform its business by acquiring other technology companies seems to be on temporary hold until the company’s buyout proposal gets resolved.

In a regulatory filing this week, Dell Inc. said its proposed buyout deal has put the company on tight constraints when it comes to adding new debt and acquiring new companies.

“Other than in transactions in the ordinary course of business or within specified dollar limits and certain other limited exceptions, Dell generally may not acquire other businesses, make investors in other persons, or sell, lease or encumber its material assets” while the buyout deal is pending, the company stated in its 10-K annual report to regulators.

That probably means Round Rock, Texas-based Dell won’t be buying any more tech companies at least in the first half of this year, analysts said.

Those analysts estimate that Dell has spent roughly $13 billion in acquiring more than two dozen companies, beginning with EqualLogic Inc. in early 2008. The biggest of those deals was the $3.9 billion that Dell spent in 2009 on computer services company Perot Systems. The second-biggest deal was the $2.4 billion it spent on Quest software in a deal completed last September. All the deals were designed to bolster Dell’s portfolio of products and services as part of its campaign to become an “end-to-end” provider of advanced computer hardware, software, services and security.

Dell ended its fiscal year on Feb. 1 with a total of $15.3 billion in cash and short-term investments and $9.1 billion in debt, including about $6 billion in long-term debt.

The company’s board on Feb. 5 agreed to a $24.4 billion buyout offer made by founder and CEO Michael Dell in collaboration with California investment firm Silver Lake Partners and software maker Microsoft Corp. Michael Dell has agreed to contribute his existing shares to the buyout along with an added $750 million. Silver Lake has agreed to invest $1.4 billion in the deal and Microsoft has agreed to make a $2 billion loan. The rest of the funds are expected to come from loans made by a consortium of banks.

Since then, several large shareholders, including Tennessee-based Southeastern Asset Management, have objected to the price the buyout group has proposed of $13.65 a share. Also this month, billionaire investor Carl Icahn has inserted himself in the deal by disclosing he acquired a substantial stake in the company and suggesting that, rather than a buyout, Dell instead use cash and debt for a $9-a-share special dividend to shareholders.

Several analysts have suggested the buyout group will have to raise its bid to about $15 a share to gain approval from shareholders. Michael Dell’s estimated 16 percent stake in the company’s stock and the shares held by senior management won’t be counted in the approval of the buyout.

The company’s “go-shop” period, in which Dell’s independent directors look for a superior offer for the company, will be completed March 22. Shortly after that, a detailed proxy report on the offering is expected to be made public. The company estimates the buyout deal could be decided in a shareholders meeting by early July. The Dell board could change its recommendation and agree to an alternative proposal for the company if it decides that alternative will be more favorable to shareholders.

This week, Dell agreed to make its shareholder list available to various investors as they try to gather support against the buyout.

In its filing, Dell Inc. said that if the buyout bid is not approved, the company might suffer “from the effects of business uncertainties.” Those adverse effects, it said, could include its ability to attract, retain and motivate key employees. It could also cause customers, suppliers, financing companies and others to seek to change existing business relationships, according to the filing.

Analyst Patrick Moorhead with Moor Insights & Strategy said he still believes the buyout will go through, even though the addition of Icahn as a shareholder adds to the uncertainty.

“The only serious threat is Carl Icahn,” Moorhead said.

Icahn has involved his investment company in a string of companies over the years, usually seeking short-term gains for shareholders.

• Kirk Ladendorf, MCT Campus