Ant-Man & the Wasp will introduce viewers to Bill Foster, a man who once worked with Hank Pym on "Project Goliath." But it's not the first time alert viewers will have heard of Project Goliath in the MCU; it was actually referenced in a blink-and-you'll-miss-it scene in 2010's Iron Man 2.
Marvel Studios likes to play the long game, dropping subtle Easter eggs than can be developed at a later date. Iron Man 2 was absolutely jam-packed with them; the film featured a reference to Wakanda, and even had a subtle nod to Project P.E.G.A.S.U.S., S.H.I.E.L.D.'s R&D division that would be unveiled two years later in The Avengers. But there's also a subtle nod to Project Goliath as well.
In Iron Man 2, Tony Stark is working hard to discover a new element - one that can cure the blood poisoning he's suffering as a result of his Arc Reactor. He finally realizes that his father discovered a new element decades ago; although JARVIS wants to run a simulation, Stark is confident this new element will solve the problem. He strolls off to take a shower, instructing JARVIS, "Get me everything on projects Pegasus, Exodus, and Goliath."
What Was Project Goliath?
The second trailer for Ant-Man & the Wasp included a scene in which Lawrence Fishburne's Bill Foster tells Scott Lang he used to be partnered with Hank on "a project named Goliath." Drawing the obvious conclusion, Scott asks how big he managed to get, to which Foster reveals that his record was 21 feet. It would actually make sense for Tony to be looking up records associated with Project Goliath; just like Hank Pym, he's attempting to discover and exploit a new element or particle.
It seems likely that Pym's project was run under the auspices of S.H.I.E.L.D., perhaps with Tony's father, Howard, providing oversight. If that's the case, it would explain why some records about the project made their way onto the so-called "Oracle Grid," with Tony knowing enough about the project to ask JARVIS to pull up the records. It's possible the project didn't go well, with Pym growing frustrated at Howard Stark's attempts to weaponize the Pym Particles. After all, in Ant-Man he shows horror at the idea of the Pym Particles ever ending up in the hands of a Stark. In Captain America: Civil War, Scott Lang reflects that Hank had told him to never trust a Stark.
This is the kind of subtle detail Marvel delight in. Sometimes this kind of Easter egg doesn't seem to lead anywhere; but that may well simply reflect the fact that Marvel Studios play the long game, and aren't in a hurry to develop the plot threads they've teased. In this case, "Project Goliath" was name-dropped a full eight years ago - and only now is being developed.