21.   The FTC alleged that the purchase would violate federal antitrust law and thwart competition in the office-supply superstore market.

22.   The FTC voted to block a Staples-Office Depot combination in early March because the new company would thwart competition in the office-supply superstore market.

23.   The Justice Department charged that, without the sale, the new Tyco would be able to thwart competition in the market for butterfly valves.

24.   The judge, Paul Luckern, said that the Gemstar patents in question were valid but that Gemstar had misused one of them in an effort to thwart competition.

25.   The suit contends that Microsoft used its market power illegally to thwart competition from its main rival for Internet browsing software, the Netscape Communications Corp.

26.   Voters and analysts also assailed the decision by the two-party Commission on Presidential Debates as an attempt to thwart competition.

27.   Without the sales, the new company would be able to thwart competition among hospitals in areas of Florida, Utah, Louisiana and Texas, the FTC said.

28.   But Powell warned companies against using their role to thwart competition.

29.   The Senate Judiciary Committee plans to open hearings in fall into whether Microsoft is improperly thwarting competition.

30.   The suit also charges that the same group of banks controls both Visa and MasterCard, thwarting competition between the two networks.