Trident Recording Studios was a British recording/mixing/engineering/mastering and cassette duplicating facility, operating under this name between 1968 and 1985. Located at 17 St. Anne's Court in London's Soho district.
Also credited as "Trident, London, England", "Trident Studios, London" or "Trident Sound Studios".

Can be identified by "TRIDENT" in the runouts (please use 'Lacquer Cut At').
Lacquer cuts for Phonodisc Ltd. (between March 1969 and January 1979) can be identified by //# T in the runouts (e.g. Clifford T. Ward - Home Thoughts From Abroad).
Lacquer cuts for PRS Ltd. (between February 1979 and ~1982) can be identified by ▽E T (e.g. Genesis - Duchess).
Lacquer cuts for PRS Ltd. (between ~1982 and mid 1988) can be identified by ▽420 V (e.g. Various - Batcave: Young Limbs And Numb Hymns).
Masterings for Lyntone Recordings Ltd. (please use 'Mastered At') can be identified by ITD (or 2TD) (e.g. The Kinks - Waterloo Sunset / Dedicated Follower Of Fashion) or IT (or 2T).

It was constructed in 1967 by Norman Sheffield and his younger brother Barry and opened in 1968.
In 1970 they installed a disc cutting suite having bought out the company London Discutting Services.
In October 1981 Trident studios closed for 3 months due to financial problems and was then sold in December 1981.
It was bought by its senior engineer, Steve Short, along with three other investors.
During the following four years the studios worked under different management until 1985, when Tape One bought the studios and renamed them to Audio One.

Side note: In 1986, Short bought out the other investors and opened Trident 2, a 25.000 sq. ft. converted theater as recording environment in the heart of the city of London.

The current residing business Trident Sound Studios, which opened in the same building in 1993 was named in recognition of the original Trident Studios.

Studio's most famous instrument was a Bechstein grand piano, featured in many recordings.

The Engineers (Recording & Mixing, Tape-Ops):
1967/1970 - Barry Sheffield
1968-69/1972 - John Smith
1968/1970 - Malcolm Toft
1969/1974 - Ken Scott
1969/1971 - Nick Smith
1969/1974 - Robin Geoffrey Cable
1969/1975 - Roy Thomas Baker
1969/1971 - Tony Platt
1970 - Alan Harris
1970/1971 - Dave Corlet
1970/1974 - David Hentschel
1970/1975 - Mike Stone
1971/1976 - Dave Hodge (4)
1971-72/1976 - Ken Thomas
1971/1975 - Neil Kernon
1972/1978 - Dennis Mackay
1972/1979 - Peter Kelsey
1972/1975 - Ted Sharp
1973/1978 - Jerry Smith (11)
1974/1978 - Peter Fielder
1975/1979 - John Brand
1975/1978 - Nick Bradford
1976/1977 - Geoff Leach
1976/1979 - Julian Taylor (3)
1976/1978 - Neil Ross
1976/1981 - Stephen Stewart-Short / Steve Short / Steven Short
1976/1980 - Stephen W. Tayler
1977/1981 - Colin Green
1977/1978 - Paul Jarvis
1977/1979 - Peter Kamlish
1977/1979 - Reno Ruocco
1978/1981 - Adam Moseley
1978/1979 - Michael Donegani
1978/1979 - Simon Hilliard
1978/1979 - Simon Wilson (2)
1979/1980 - Chris Stone (3)
1979/1981 - Craig Milliner
1979/1980 - Paul Frindle

Disc Cutting / Mastering Engineers:
1970/1972 - Norman Austin (perhaps Norman Austin (2) ?)
1970/1986 - Ray Staff - Signatures: RASIN, RASPUTIN, RAYS, RAZEL and variations thereof
1971/1976 - Bob Hill (9) - Signatures: AUNTIE B, BOBIL, HILTOP and variations thereof
1971/1974 - Howard Thompson (3) - Signatures: KIP, KIPPER and variations thereof
1971/1976 - Tim Young
1972/1973 - Brian Snelling
1973/1978 - John Dent - Signatures: JONZ and variations thereof
1978/1981 - Steve Angel - Signatures: SA or S.A.
1979 - Geoff Tuck - Signatures: GEOFF or GEOFF's or G.T. (please do not confuse with Geoff Pesche!!!)
post-1981 - Barry Grint - Signatures: BAZZA and variations thereof

Maintenance Engineers:
1968/1972 - Barry Porter
1968/1975 - Ron Goodwin
1970/1981 - Peter Booth
1970/1976 - Piers Blastkett
1974/1980 - Barry Spencer
1974/1976 - Bernie Spratt (maintenance engineer, helped to build the copy, cutting and mixing rooms)
1977/1980 - Henry Edwards (2) (technical manager of the recording, mixing and cutting rooms)

Studio Management:
1967/1970 - Barry Sheffield
1968/1975 - Penny Kramer
1970/1972 - Malcolm Toft
1970/1981 - Peter Booth
1972/1974 - Bob Hill (9)
1972/1974 - Ray Richardson

Other:
post-1981 - Pete Cippa (Copy Room engineer)