/portfolio-management-systems

name: portfolio-management-systems
description: "Select, configure, and operate portfolio management systems for advisory firms, covering model portfolios, UMA/sleeve management, drift monitoring, rebalancing, and custodian data feeds. Use when the user asks about choosing a PMS platform, building or distributing model portfolios, implementing UMA or sleeve-based management, setting drift monitoring thresholds, aggregating held-away assets, reconciling PMS with custodian records, configuring PMS-based billing, or troubleshooting custodian feed issues. Also trigger when users mention 'portfolio management system', 'Orion', 'Black Diamond', 'Tamarac', 'Addepar', 'Advent APX', 'model portfolio', 'sleeve management', 'rebalancing engine', 'custodian feed', or 'PMS migration'."

Portfolio Management Systems

Core Concepts

> Expanded detail for each numbered section below lives in > [references/platform-details.md](references/platform-details.md). Load it when the task needs: > §1 the platform comparison table or IBOR/OBOR reconciliation dimensions; §2 full model > specification, governance steps, or marketplace detail; §3 UMA cash-waterfall rules or the > UMA/SMA/wrap comparison table; §4 drift measurement formulas, threshold configurations, or > tax-aware rebalancing logic; §5 aggregation data sources and data-quality failure modes; > §6 break-resolution workflow, corporate-action types, or cost basis methods; §8 daily vs. > monthly calculation and benchmark tracking detail; §10 the custodian data-flow table, > integration methods, and feed timing. (Reference §7 trading and §9 billing are pointers to > the order-management-advisor and fee-billing skills — load those skills directly instead.)

1. Portfolio Management System Architecture

The PMS is the operational nerve center of an advisory practice, orchestrating data flow between custodians, trading platforms, reporting engines, CRM, and planning tools. Core functions include portfolio construction, model management, rebalancing, trading, performance reporting, and billing. Major platforms: Orion, Black Diamond, Tamarac, Addepar, Morningstar Direct, Advent/APX. The PMS serves as the firm's Investment Book of Record (IBOR), which must be reconciled daily against the custodian's Official Book of Record (OBOR).

2. Model Portfolio Management

Model portfolios define target allocations (asset classes, securities, weights) applied consistently across client accounts. Types include strategic (SAA), tactical (TAA overlays), and specialty models (income, ESG, tax-managed). Firms typically use a two-tier hierarchy (firm-level + advisor-customized). Model changes trigger versioning, account identification, trade proposal generation, and tax-aware transition. Third-party model marketplaces (BlackRock, DFA, Vanguard, PIMCO) allow smaller firms to access institutional-quality investment management.

3. Sleeve-Based and UMA Architecture

Unified Managed Accounts (UMAs) divide a single custodial account into virtual sub-accounts (sleeves), each following its own strategy or manager. Benefits: cross-sleeve tax optimization, simplified reporting, reduced account proliferation, and unified cash management. Cash waterfall rules govern deposits, withdrawals, and income allocation across sleeves. UMAs differ from SMAs (single-strategy, one manager) and mutual fund wraps (indirect ownership, limited customization). Typical minimums: $250K-$1M+.

4. Drift Monitoring and Rebalancing

Drift is the divergence of actual weights from targets caused by differential returns and cash flows. Measured as absolute drift (percentage-point difference) or relative drift (percentage of target). Threshold configurations range from conservative (3%/15%) to permissive (7%/30%). Rebalancing approaches: calendar-based, threshold-based, opportunistic (cash-flow-directed), and hybrid. Tax-aware rebalancing incorporates capital gains minimization, loss harvesting, wash sale avoidance, and gain budgets.

5. Held-Away Asset Aggregation

A complete client picture requires visibility into all assets, including employer plans, stock options, RSUs, bank accounts, and accounts at other custodians. Data sources: aggregation services (Plaid, Yodlee, MX, ByAllAccounts), custodian feeds, manual entry, and employer plan integrations. Challenges include data staleness, categorization errors, and broken connections. The PMS should provide both managed-only and total-household reporting views.

6. Portfolio Accounting and Reconciliation

Portfolio accounting tracks positions, transactions, cost basis, cash flows, and accrued income. Daily reconciliation compares PMS against custodian across three dimensions: positions, transactions, and cash. Breaks require classification, root-cause diagnosis, correction, and documentation. Common break sources: corporate actions (splits, mergers, spin-offs, DRIP), trade settlement timing, and data feed issues. Cost basis methods: specific identification, FIFO, and average cost.

7. Trading and Order Management Integration

The PMS generates trade proposals from model changes, rebalancing triggers, cash flows, and ad-hoc instructions. In larger firms, trades flow through a separate OMS for compliance checks, block aggregation, and execution routing. Block trading aggregates orders across accounts for best execution with pro-rata allocation. Pre-trade checks cover restricted securities, concentration limits, client restrictions, regulatory limits, and cash minimums. Implementation methods: direct custodian trading, third-party EMS, and mutual fund trading platforms.

8. Performance Calculation Engine

The PMS computes returns at multiple levels: security, sleeve, account, household, model, composite, and firm. TWR (time-weighted) eliminates cash flow impact for manager evaluation and GIPS compliance. MWR (money-weighted/IRR) reflects the investor's actual experience. Daily performance provides the most precise TWR; month