Futurestock - S4-E9
Corrected entry: After the 80's guy dies, Fry decides to vote against selling the company to Mom. 80's guy owned 51% of the shares while Mom and her sons owned the rest, putting the "Yes" option at 99.99% (one son made an error). But when Fry votes "No", Mom's 49% has swapped over to the "No" option to give it 100%- indicating Mom didn't want the sale to go through either.
Correction: The 49% in the "No" section was from the rest of Planet Express voting against selling the company. Mom tells Fry he's an idiot for wanting to choose not to sell, and leaves the stage during Fry's speech about making the Professor CEO again. Therefore her 49.99% was removed from the "Yes" before Fry even voted, leaving the 49% in "No" from Amy, Leela, Bender, and Hermes from earlier.