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Portfolio Drift

Portfolio drift is the gap between a portfolio's current allocations and its target policy weights, created as markets move, contributions arrive, and withdrawals occur. Unaddressed drift means clients are holding a materially different risk profile than the one documented in ...
Allocation drift Strategy drift Policy drift

Why examiners care

Common cause
Equity bull run shifts a 60/40 portfolio to 75/25 over 12 months. No rebalancing trigger was set.
What the examiner sees
Portfolio materially inconsistent with stated IPS — potential suitability violation.
Defensible response
Documented drift threshold policy, evidence of periodic review, and a supervisory sign-off trail.

How drift happens

Drift is mechanical. A 60/40 portfolio that returns 20% on equities and 2% on fixed income in a year ends closer to 67/33. Without rebalancing, the portfolio's actual risk profile diverges from the policy stated in the client's investment policy statement.

Where drift creates compliance exposure

Drift becomes an examination issue when the firm cannot demonstrate three things:

  • The drift is being measured against the documented policy, not just observed casually.
  • The firm has a defined response — automatic rebalancing, exception escalation, or documented client decision to allow the drift.
  • The decisions are timestamped and tied back to the client's suitability profile.

Common drift triggers worth tracking

  1. Equity allocation moving outside the policy band (e.g., 60% target, 50–70% allowed).
  2. Single-position growth pushing into concentration territory.
  3. Cash building up beyond planned levels — often a sign of missed reinvestment.
  4. Liquidity bucket shrinking as the client's spending horizon shortens.
  5. Tax-aware drift — letting positions ride to harvest losses or defer gains.

Drift versus performance

Drift is about alignment with policy, not about return. A portfolio can outperform its benchmark and still have drifted into a risk profile the client did not consent to. The compliance question is alignment, not performance.

How StratiFi thinks about portfolio drift

The firms that defend drift well are not the ones with the strictest auto-rebalancing rules — they are the ones whose drift policy is connected to each client's stated risk tolerance, documented in the IPS, and reviewed on a written cadence. When a portfolio breaches a band, the next action is a routine decision, not an emergency.

Frequently asked questions

  • How much drift is acceptable before rebalancing?

    The IPS sets the band — typically 5 to 10 percentage points off target for major asset classes. The compliance issue is not the band itself; it's whether breaches are detected, documented, and acted on. A 60% equity target with a 5% band triggers review at 55% or 65%.
  • Does the SEC examine portfolio drift?

    Yes. Persistent drift inconsistent with the documented IPS is a recurring SEC finding. Examiners look for documented drift thresholds, evidence of periodic review, and the supervisory record showing what the firm did when an account breached its band.
  • What's the difference between account-level and household-level drift?

    Account-level drift is calculated for one account against its policy. Household-level drift aggregates across all accounts a client holds with the firm — a single household can be on policy in aggregate while individual accounts drift dramatically. Multi-level monitoring catches both.
  • Is drift always bad?

    No. Tax-loss harvesting, letting a winner run with documented client consent, or holding cash for upcoming distributions all create explainable drift. The compliance issue is uncontrolled drift the firm cannot explain or did not notice.