Staples has updated their price matching policy to clearly state that they no longer price match. On the pricing and promotions page it now states:

Does Staples match competitor’s prices?

No. Staples.com does not offer a price match policy. Staples.com policies vary from those in store. Please see a store associate at our customer service desk for in store price match policies.

Previously the page included a full F.A.Q section on price matching and the restrictions around it (can be viewed on wayback machine here). It looks like this is only affecting Staples.com as the in store ads are still displaying the 110% price match information.