Sam Altman's little brother Jack is an entrepreneur, too. And yes, his startup is a YC grad. : Jack Altman, whose resume includes a stint as vice president of business development at Teespring, has raised $15 million in Series B funding for his startup, Lattice, a modern approach to corporate goal setting. Shasta Ventures led the round, with participation from Thrive Capital, Khosla Ventures and Y Combinator, the latter being the organization his brother led as president until very recently.