Tyco's board is still reeling from criminal indictments of three former senior executives.
Critics have denounced York's appointment to the board, saying his business dealings at Apple, where he is a director, raise the same conflict of interest issues that caused Tyco to part company with members of its board.
In September, New York prosecutors charged chief financial officer Mark Swartz and former Tyco chief executive L Dennis Kozlowski with stealing $170 million from Tyco in unauthorized compensation, and reaping an additional $430 million in unlawful gains through stock sales. Swartz and Kozlowski have pleaded not guilty.
Conflict York sits on Apple's compensation committee, but observers have claimed this creates a conflict of interest with his board duties.
While York was on Apple's board, Apple CEO Steve Jobs received a $90 million Gulfstream jet for the two-and-a-half years he served without pay – although there is no suggestion this was unauthorized. James Voye, a pension fund representative for the International Brotherhood of Electrical Workers union, said: "It was the old boys network at its worst."
However, Tyco investors have backed York. Ralph Whitworth, whose Relational Investors owns several million Tyco shares, said: "The guy [York] has impeccable ethics and impeccable integrity, plus he's brilliant."
Whitworth told Reuters that York sought his advice on whether he should remain on Apple's board as he negotiated to buy Micro Warehouse in 2000. Apple, in the midst of a turnaround plan, encouraged York to stay, Whitworth said.
York's firm Micro Warehouse accounted for almost three per cent of the Apple's sales last year.
Apple was recently named one of the worst US corporate boards in a BusinessWeek survey.
In June, Tyco chairman and chief executive Dennis Kozlowski resigned after being investigated for tax evasion.
Tyco’s specialities include electronics, fire and security services, and healthcare products.