LinkedIn uses on a second-price auction, which means you will pay a penny above the second-highest price.

This statement is TRUE. LinkedIn's ad auction operates on a second-price model, also known as a Vickrey auction. In this system, the winning bidder pays an amount equal to the second-highest bid plus a small increment (often a penny). This mechanism encourages advertisers to bid their true value for an impression, as bidding higher than their true value risks overpaying, and bidding lower risks losing the impression. This system aims to maximize advertiser value while ensuring fair competition.