Private markets implementation and liquidity: A practical framework for DC plans

Interest in private markets within target date funds is rising as implementation becomes more feasible. A central challenge remains liquidity: integrating illiquid assets into daily-valued DC structures without diluting any potential illiquidity premium. This paper outlines practical considerations that can help inform how investors approach sizing, structuring, and governing private markets exposure.

Interest in incorporating private markets within target date funds has accelerated, driven less by changes in the long-term risk/return case than by advances on implementation and frameworks for evaluation. Despite these developments, a fundamental challenge remains: reconciling illiquid assets with the daily valued, participant driven structure of DC plans.

While evergreen structures with periodic redemptions have broadened access to private market assets, those assets generally feature constrained liquidity—therefore liquidity remains an important diligence and design consideration for DC plans. Implementation considerations differ across strategies and mandate sizes, but without sufficient confidence in the liquidity profile of an investment, private market allocations may be limited in size even for those who believe most strongly in the investment case. Yet over engineering for liquidity, through large cash buffers or similar mechanisms, may reduce the potential benefits investors seek from private market exposure.

While participant level liquidity is generally supported by the structure of target date funds being comprised primarily of liquid public assets, complete plan level liquidity cannot be assured at all times. Thoughtful structuring and governance can help investors assess and manage these tradeoffs, supporting a more measured evaluation of potential benefits and implementation risks.

Amidst an abundance of noise around private market liquidity in retail vehicles, what follows are five core considerations of liquidity that inform State Street’s due diligence process and help guide the integration of private markets exposure within its target date strategies.

1. Scale as a foundation for liquidity management

When constructing a target date fund with a private markets allocation, the glidepath manager can start from two distinct approaches. A bespoke private markets portfolio may offer greater control over portfolio construction and liquidity terms, but it also introduces the challenge of building scale. For private market evergreen vehicles, liquidity, diversification and efficiency all may improve non-linearly as assets grow, presenting potential challenges for early adopters. As a result, we adopted an alternative approach, prioritizing demonstrated scale and operational maturity within the private markets vehicle as critical when considering inclusion.

In evergreen private market structures, scale may directly affect a manager’s ability to meet redemptions without relying on forced asset sales. Larger platforms may benefit from broader opportunity sets, deeper origination platforms, and greater flexibility in managing inflows and outflows across investors groups that would typically be more diversified for scaled products. As a general observation, most private market evergreen vehicles offer, at their discretion, a percentage of fund Net Asset Value to investors periodically, typically either monthly or quarterly. In what may be a simple but important point, a 5% allocation in a $5 billion portfolio with 100 investors may offer relatively greater flexibility in managing liquidity than a 5% allocation in a $100 million portfolio with 2 investors, although this can vary depending on market conditions and other factors.

That said, scale alone is not a guarantee of liquidity. Recent periods of stress across private markets have demonstrated that even large funds can face challenges when valuation uncertainty coincides with elevated redemption demand. As a result, scale is often viewed as a necessary—but not sufficient—condition. We believe it should be paired with disciplined portfolio construction, conservative liquidity assumptions, and explicit governance mechanisms designed to protect long-term investors.

2. Diversification across assets and vintage years

Private markets are not immune to cyclical stress, nor do they experience it uniformly. Liquidity pressures often emerge unevenly—by sector, geography, or vintage year.

Diversification, therefore, plays a central role in our evaluation. We prioritize approaches that combine exposure across multiple private asset types and investment vintages, rather than relying on a single segment or deployment period. In our view, diversification may improve the predictability of cash flows and reduce reliance on any one exit environment to meet redemption needs.

This consideration remains particularly important given recent experiences in private credit and private real estate. In private credit, stress was most visible in levered direct lending strategies facing maturity walls and slower capital repayment, while in private real estate, gating became more common as appraisal based NAVs lagged public market repricing and investor outflows accelerated. These episodes reinforced the risk of relying on single asset liquidity profiles during periods of market dislocation. A diversified, multi asset approach—spanning strategies with differentiated cash flow drivers, duration, and sensitivity to transaction volumes—may be more resilient to these dynamics and better aligned with the cash flows that target date funds require for ongoing rebalancing and plan level redemptions.

3. Investor base alignment and behavioral liquidity risk

Liquidity outcomes are shaped as much by investors as by assets. The recent experience of private credit funds with a high concentration of retail-oriented investors highlights the risk that capital with shorter behavioral time horizons can amplify redemption pressure during periods of market stress. For DC investors, this distinction is critical. Target date funds represent structurally long-term capital with predictable contribution and withdrawal patterns. Aligning that capital with similarly patient investor bases may help mitigate liquidity mismatch risk.

Just because the intended time horizon of the target date fund often matches that of private market investments doesn’t necessarily mean that every investor in the private market vehicle shares that same time horizon. Funds with investors diversified across geographies and investor types—for example, a mix of institutional, insurance, and wealth capital—may be more diversified in their liquidity profile than funds concentrated in a narrow or homogeneous investor segment. No evergreen fund that mixes investor types is immune from redemption requests, but a concentrated investor profile can increase the risk that redemption behavior becomes correlated during periods of stress, testing liquidity precisely when it is most valuable.

4. Cash flow as the cornerstone

Ultimately, liquidity must be funded. Strategies that depend primarily on episodic realizations—such as asset sales or capital markets exits—are inherently more exposed to timing risk. By contrast, portfolios that generate steady, repeatable cash flows may be better positioned to support periodic liquidity.

As part of our evaluation, we placed significant weight on the underlying cash-flow characteristics of private market exposures. Income-generating strategies—particularly those supported by contractual payments—may provide a mechanism for meeting redemption requests without the potential to impair liquidity across the entire portfolio.

Equally important was transparency around liquidity terms. The size, expense, and intended use case of lines of credit, paired with redemption features that explicitly recognize the limits of asset liquidity, including the use of caps when necessary, were viewed as a strength rather than a weakness.

5. Balancing liquidity with cash drag

Institutional investors have long understood that dispersion across private managers is significant. Multiple third-party analyses using private market datasets show that the spread between top- and bottom-quartile outcomes in private markets is materially wider than in public markets. This dispersion reinforces that manager selection may be central to expected outcomes.

Evergreen and semi-liquid structures add an additional dimension: continuous deployment. Unlike drawdown funds, evergreen vehicles must absorb ongoing subscriptions while seeking to meet periodic liquidity needs. When high-quality opportunities are scarce, managers may face a trade-off between holding elevated cash balances (creating cash drag) or deploying into lower-conviction opportunities simply to remain invested. Both outcomes can present challenes—either through diluted returns or weakened underwriting standards. As these structures scale, we believe the ability to source deals, allocate capital selectively during periods of market dislocation, and manage cash efficiently becomes a defining capability that may play a critical role in the long-term efficacy of these strategies.

From framework to implementation: Key takeaways

Thoughtfully incorporating private markets into a target date glidepath is more than an investment or optimization exercise. Practical considerations around liquidity (both with respect to redemptions and deployment) provide guardrails in the level of exposure that can be realistically achieved. Through our research, we observed that, based on our assumptions, a consistent 10% allocation to a diversified, multi-asset private market portfolio throughout participants careers may influence retirement outcomes differently than varying allocations to single sleeve exposures (e.g. private equity, credit and real assets), based on our assumptions. This reflected our assessment of suitability, in particular the liquidity profile of the exposures along the glidepath. Single sleeve exposures had the potential for more precision, but in our analysis also led to lower weights due to the idiosyncratic risks detailed throughout this paper. Concern over being a forced buyer or seller of each asset class based on the relative point in the glidepath that each asset class was held further pointed our analysis in favor of a multi-asset approach.

The framework we have outlined—focused on scale, diversification, investor alignment, cash flow, and disciplined liquidity management—helped guide our evaluation and selection of a private markets allocation within the State Street Target Retirement IndexPlus Strategies. We look forward to continuing to share our findings as the space evolves.