BABCOCK

Valued at £3.6billion and employs 35,750 staff. Made £362.1million profit last year.

Dating back to 1891, the key engineering firm and defence contractor has capacity to refit the Royal Navy’s entire submarine fleet.

Work includes decommissioning nuclear plants and building UK’s new aircraft carriers.

Babcock designed the Alexandra Palace Tower, source of the BBC’s first public TV transmission in 1936.