Heat oil in a large pot over medium heat. Sauté garlic in hot oil until tender, about 1 minute.
Pour in white wine; bring to a boil. Cook until wine is reduced by half.
Add clams, cover the pot, and steam just until clams start to open. Add butter, cover the pot, and continue cooking until most or all of the clams open. Discard any clams that do not open.
Transfer clams and broth to 2 large bowls. Sprinkle with chopped parsley and serve.