2 Ali Hirsa & Massoud Heidari
manager directs investments through a sub-management contract. In most cases, SMAs and
the Fund have the same investment objective, and the SMAs seek to replicate the returns of
the Fund.
In a Fund, all trades are tracked and accounted for at the Fund level, and gross returns
of these trades are distributed among all clients in an identical manner. In contrast, when
dealing with SMAs all trades need to be allocated between SMAs in a proportional manner
first, and the returns are calculated for each individual SMA separately. Have in mind this is
also the case for block trades [2], as the Fund manager still needs to allocate those block
trades into all accounts (in this case to the Fund also).
In principle, this is a straightforward problem: allocate trades proportional to relative
account size, and then calculate returns. However, in practice, since trades hardly take place
at a single price, or at the same time, and because one cannot divide securities into random
fractions, allocations need to resort to rounding, which, as we will show, is the source of
divergence in returns among accounts (and between SMAs and the Fund). For block trades,
we can imagine situations where the manager pre-designs trading sizes to avoid fractional
allocation and rounding but as the number of accounts increases with different account
sizes would make it very challenging. The rounding forces a choice between accounts to be
over-allocated and accounts to be under-allocated, which leads to uneven distribution of
returns. Furthermore, repeated application of a mechanical decision rule for the over/under
allocation of trades (bias) will often-times lead to larger and larger divergence of returns
among accounts and between the SMAs and the Fund. To prevent large tracking errors,
and to provide all accounts with equitable and even distribution of returns, the industry
has adopted various approaches for allocation of trades, generally processed, at the end
of each trading day. This is often a manual and time-consuming process - the art of trade
allocation - and does procedurally tries to ensure fair and equitable treatment of all accounts.
The general premise is that the fair and equitable rationale is met via rigorously applied
procedures that do not exhibit outward biases towards any of the accounts. However, as we
will note in the paper, using any of the prevalent methodologies results in return divergence
between accounts and the premise that the accounts balance out over time maybe flawed.
Thus our objective in this paper is to shed light on the problem of trade being allocated
across multiple accounts or other vehicles. In specific, despite the mathematical rigor of the
underlying process, we will use some simple examples to show the source of the problem,
which leads to the divergence of returns, and present a solution to remedy the problem.
2NFA/CFTC Compliance Rule
Although there are no general methodologies for trade allocation, the NFA Compliance Rule
2-10/CFTC Regulation 1.35, the allocation of bunched orders for multiple accounts [5], sets
out three principles that should guide the allocation procedures: (1) fairness, (2) objectivity,
and (3) timeliness. In the same document, they provide examples of procedures that satisfy
these objectives. Here is an excerpt from the NFA/CFTC Compliance Rule:
“NFA Compliance Rule 2-10 adopts by reference CFTC Regulation 1.35, Among other things, this
regulation requires that bunched orders be allocated in a fair and equitable manner so that no account
or group of accounts consistently receives favorable or unfavorable treatment over time. The rule
further provides that Eligible Account Managers bear the responsibility for the fair and equitable
allocation of bunched orders.” CFTC Regulation 1.35(b)(5)