Can Exchange Rebates Help Align Broker and Client Incentives?

The SEC transaction fee pilot has received considerable attention recently. The main issues involved are well-known.[1] But in a nutshell, the fee pilot aims to gauge how a fee cap reduction and (separately) an elimination of rebates would impact markets. Many on the buyside view the proposal favorably, noting that both would reduce the incentives of brokers to route orders to high rebate venues. Critics have noted the pilot could lead to increased spreads and/or decreased depths due to reduced incentives to provide liquidity. Plus, implementing the pilot involves adding complexity to an already extremely complex marketplace. And from a competitive perspective, leaving dark pools and other non-exchange entities out of the pilot puts them at a relative advantage in pilot stocks, which could have a detrimental effect on price discovery as volume shifts to off-exchange venues.

Can rebates actually help align broker and client incentives?

While much has been made of the adverse incentive effects rebates have on broker routing, relatively little attention has been paid to the potential beneficial aspects of rebates on broker incentives. Specifically, in the same way rebates give market makers greater incentives to provide liquidity, rebates provide brokers with similar incentives to provide liquidity via greater use of passive make orders relative to aggressive take orders. A key consequence of increased passive trading is the potential for better fill prices for clients, leading to more favorable performance on average.[2]

An example of this can be seen in the context of algorithmic trading. Algorithms often have discretion over the mix of make and take child orders they send out to execute a parent order. To the extent that rebates incentivize brokers to trade passively via make orders, they can indirectly result in improved algo performance if the bias toward passive pricing leads to better fill prices and reduced market impact.[3] Contrast this to a child order pricing strategy where make and take orders have identical exchange fees. In that setting, a broker would essentially be indifferent from a fee perspective between sending make or take orders. And when other incentives are taken into account, the broker may actually prefer aggressive take orders over passive make orders since take orders generate commissions for the broker with certainty, while an unfilled make orders generate no commissions.[4]

Will this favorable incentive go away if the SEC bans rebates?

It should be noted that a make rebate is not entirely necessary for a broker to be incentivized to use passive make orders. All that is required is that the cost of a take order exceed the cost of a make order. Of course, the magnitude of the difference has an impact on the strength of the incentive. Eliminating rebates and/or reducing the fee cap would shrink the difference between the make and take fees, thereby reducing – but not eliminating – the incentive for brokers to prefer make orders to take orders.

But these incentives alone may not be enough to improve performance

To be clear, the argument above does not necessarily imply that incentivizing passive trading would actually improve buyside trading performance. For example, a broker who simply routes its make orders to the highest fee venues will not improve performance, should the lower fill rates lead to sufficiently high opportunity costs. But, in most cases, the cost differential between the optimal and the suboptimal make venues is typically significantly smaller than the fee differential between make and take orders.[5] Consequently, it is more likely that other considerations could sway a broker to route its make orders optimally.

For example, suppose a buyside trader submits an order to a brokers algorithm with an instruction to complete the order fully (e.g., unconstrained VWAP). The must complete instruction actually incentivizes the algorithm to choose the venue that maximizes fill rates for its make orders. To see how, consider what would happen if the algorithm routed to a high rebate venue that had a low fill rate. If the make order does not fill, the algorithm would eventually need to resort to higher-cost take orders to stay on schedule and to ensure completion. And because the optimal make venue is likely to be cheaper than the cheapest take venue, the algorithm will still prefer passive trading to aggressive trading, on average.

An interesting corollary to this argument is that, if each exchange set its make and take fees to be identical, brokers would not only lose the incentive to submit make orders, but the perverse broker incentives motivating the fee pilot could still exist. Specifically, if each exchanges make and take fee were equal, but these fees still varied across exchanges, brokers would still prefer routing to the low fee venue. So long as differences in fees exist across venues, simply abolishing rebates and/or reducing the fee cap will not eliminate broker incentives to route to the lowest cost venue.[6]

A second corollary is that inverted venues may provide incentives for brokers to prefer take orders, even if the broker could have filled the order passively at a better price. For example, suppose an inverted market is at the best opposite side quote and the optimal make venue is also an inverted venue. In this case, the broker is incentivized to take liquidity and earn a rebate rather than route to the optimal make venue and pay a fee.

Commissions speak louder than rebates

The discussion thus far has focused entirely on how broker incentives relate to fees. But there is another, equally critical aspect of this discussion. Brokers are concerned not simply with minimizing costs. Rather, they are concerned with maximizing net commissions. For a fixed level of commissions, brokers do have an incentive to reduce exchange fees by maximizing rebates (or minimizing costs), as noted above. But using that logic, brokers also have incentives to hire cheap inexperienced staff, deploy subpar technology, use higher latency SIP data, understaff the support desk, etc. But brokers ignore these incentives if other stronger offsetting incentives exist, namely that taking these actions could have a significant, negative effect on commission revenue.

The implication of this is that, even in the absence of regulation, buyside traders themselves can help mitigate the adverse incentives brokers have to route inefficiently by using commissions as a carrot… and a stick. Buyside traders can reward those brokers who focus on execution quality over rebate maximization by routing more flow. And for brokers that put their own interests ahead the clients, buyside traders can simply reduce flow or stop allocating orders to those brokers entirely.[7] But to do this effectively, buyside traders must figure out which brokers are providing superior performance even in the presence of these potential conflicts.

Key Takeaway

While brokers can have incentives to take actions at the expense of client performance, buyside traders have an even stronger tool to combat these incentives: performance-based broker order allocation. Determining which brokers are focusing on performance can be done partially on a qualitative basis, by better understanding how brokers route their orders. The increased level of disclosure mandated by the SEC surrounding routing incentives will be quite useful in this regard.[8] But to really incentivize brokers to prioritize performance over rebate maximization, buyside traders must allocate orders based on performance itself . And this requires buyside traders to create a process to measure performance meaningfully and on an ongoing basis. For example, a client could use an Algo Wheel to randomize orders across brokers in a controlled manner, as discussed in a prior post.[9] Many clients have already set up in-house expertise to evaluate broker performance. Others rely on external vendors, like The Bacidore Group, LLC, to assist them in developing performance measurement systems or to measure performance on their behalf. But regardless, performance measurement is key to ensuring brokers focus on trading performance and not on cost minimization.

[1] For a complete discussion of the issues, see

[2] This could also lead to enhanced market quality as well, as more passive trading of institutional orders increases the posted quantity in the market and provides competition to market makers and other liquidity providers.

[3] Of course, for orders with high alpha, traders or PMs with high risk aversion, etc., the increased passive trading could actually increase cost (in the former case) or generate a poor risk-return trade off (in the latter case).

[4] Furthermore, algorithmic providers may have less incentive to invest in their passive smart routers, as such systems require continuous monitoring of markets, frequent updating of limit prices and sizes, more sophisticated models, etc.

[5] For example, suppose a take order cost upward of 30 mils, while a make order could generate a rebate of 29 mils, for a 59 mil difference. Even if an inverted venue turns out to be the optimal market, the broker is typically still better off posting at an inverted venue and paying a fee than using a take order and paying an even steeper take fee. (An exception, of course, is when the inverted venue is offering the best take price, since the broker may be incentivized to take liquidity and earn a rebate with certainty).

[6] Unless of course, all exchanges converge to the same fee schedule.

[7] Some buyside clients may not be able to avoid routing at least some flow to a given broker, however. In the U.S., for example, buyside traders may need to route to a specific broker to pay for research, to compensate their prime broker for services, etc.

[8] See for details.

[9] See our earlier blog post on algo wheels here: