Wholesale market makers pay for retail options orders that must be executed on exchanges. Payment for order flow (PFOF) wholesalers compete via price improvement in exchange auctions. To attract retail orders, wholesalers run more auctions when their recent price improvement has been lower. However, auction price improvement lowers market maker revenues. Wholesalers earn revenues to pay PFOF in nonauction trades where their designated market maker status increases their execution priority. While some auctions produce substantial price improvement, most do not have multiple bidders offering meaningful price improvement. Overall, options market structure better promotes competition in auctions than in nonauctions.

We examine hidden orders usage by algorithmic traders (ATs) and nonATs. ATs extensively use hidden orders but of smaller size than nonATs, who are the primary contributors to hidden volume. ATs’ relative share of hidden volume decreases with volatility, adverse selection costs, and the relative tick-size. Proprietary ATs (HFTs), who differ from agency ATs (AATs) in their information sets and potential gains from trade, hide orders to reduce competition for liquidity provision, whereas AATs use hidden orders to conceal information in their more informed orders and manage picking-off risk. Finally, superior technology provides limited benefit for hidden order execution.

Dealer quotes in corporate bonds, though indicative, lower trading costs and increase trading volume. Dealers offering higher quality quotes attract more order flow and execute trades at favorable prices. Dealers advertise quotes to manage their inventories and attract orders from nonrelationship clients. However, quote competition is imperfect. The best quotes often fail to attract orders, and trade‐throughs are common. Nevertheless, quote competition is important as clients exploit quotes from other dealers in negotiations, forcing dealers with lower quality quotes to offer price improvements. Quoting is not a zero‐sum game, as more active bond‐level quoting leads to more bond‐level trading.