The phrase "as having employed" is correct and usable in written English.
It can be used when referring to someone or something that has been engaged or utilized in a particular context or situation.
Example: "The committee recognized the team as having employed innovative strategies to improve efficiency."
Alternatives: "as having utilized" or "as having engaged".
Mr. Rawlings, in the interview Sunday, described Mr. Johnson as having employed tactics designed to cause as much harm to people as possible.
Mayor Mike Rawlings of Dallas, in an interview near the shooting site, described Mr. Johnson as having employed tactics designed to cause as much harm to people as possible.
Colalucci describes Michelangelo as having employed the best possible fresco techniques, as described by Vasari.
Studies of diesel exhaust and lung cancer and metal machining oils are cited as having employed advanced industrial hygiene and epidemiologic methods for studies of complex mixtures.
A small commercial fishery in southern California supplies Pacific electric rays for research purposes; as of 2005 this fishery may have employed as few as two fishers.
Just as Pakistan has employed its usefulness to the United States to good effect, India can now threaten to undo that usefulness and imperil the fight against Al Qaeda.
Architectural projects in countries such as Germany and Switzerland have employed algae to insulate buildings and generate energy.
This huge works had employed as many as 5,000 people making armaments in the War; now it had only 25.
No critic has so publicly taunted the Communist Party as Mr. Ai, even as security officers have employed a variety of tactics in a continuing campaign to cow him.
It was as though Raymond Domenech had employed a half-time psychologist.
It is as if someone had employed a team of circus clowns to build the set of some wildly ambitious opera.
