announced yesterday that it would acquire Mallinckrodt Inc., a global healthcare company, for approximately $4.2 billion.

The purchase, which is subject to regulatory review and approval by Mallinckrodt shareholders, will involve a share exchange such that Mallinckrodt shareholders will receive Tyco shares valued at $47.50 each for each share of Mallinckrodt.

Mallinckrodt, which had revenues of $2.6 billion last year, has substantial market positions in respiratory care, diagnostic imaging and analgesic pharmaceuticals.

"Mallinckrodt provides an excellent strategic fit with Tyco Healthcare, with complimentary products, services and geographic reach, as well as platforms for future growth,'' said Tyco Chairman and CEO L. Dennis Kozlowski.

A Tyco Press release said the acquisition would make Tyco Healthcare the global leader in respiratory care. Mallickrodt is also a leader in developing new products in the alternate care markets for home oxygen therapy, sleep therapy and portable ventilation.

"The combined strength of Mallinckrodt's products and Tyco's global sales and service organisation will allow Tyco Healthcare to leverage its international infrastructure and enhance penetration in key geographic markets,'' said Mr.

Kozlowski.

"Mallinckrodt's strong positions in the respiratory, pharmaceuticals and diagnostic imaging segments will provide Tyco with excellent platforms for future acquisitions and licensing agreements.'' Tyco operates in more than 80 countries with fiscal revenues for 2000 expected to reach $28 billion. Shares in the company traded higher on the NYSE yesterday, ending up 1 to end at $46.50. News of the deal sent Mallinckrodt shares down 1 1/2 to $43.50.