What are the most common purchase gate constraints on LMO trades in broadly syndicated CLOs?
TL;DR: A Loss Mitigation Obligation purchase in a broadly syndicated CLO has to clear, in order, five binding constraints: a definitional gate (related-obligor link, loss-mitigation purpose, manager designation at acquisition); the aggregate LMO investment cap (typically 2–5% of the Collateral Principal Amount); a source-of-funds restriction; a coverage-test "maintain or improve" check; and any equity sub-cap inside the headline LMO bucket. Outside the reinvestment period, additional conditions stack on top.
The LMO regime gives a CLO manager a controlled set of tools to defend an existing portfolio position — rescue financings, DIP loans, equity-for-debt swaps — without pushing the trade through the standard eligibility and concentration rules that govern an ordinary collateral purchase. The trade-off is that an LMO purchase has to clear its own set of gates, most of which are bespoke to the LMO framework and not interchangeable with general Collateral Obligation eligibility tests.
For a senior analyst pricing or modelling an LMO trade, the operationally binding constraints fall into a consistent rank order across most recent US BSL indentures. The order below reflects how often each binds in practice — the definitional gate fails first, the cap binds most often once a deal is inside the regime, and the coverage-test check is the variable that most frequently forces a trade to be resized rather than refused.
Why this varies across deals
LMO purchase gates are one of the more drafted-around areas of US BSL CLO documentation. Four variables drive material variation:
Vintage. The current LMO framework crystallised from around 2019, drawing on LSTA model provisions, and its use accelerated through the 2020–21 distress cycle. Earlier indentures frequently lack a dedicated LMO regime, forcing rescue investments through "equity security" or "workout loan" provisions with different — usually tighter — gates.
Cap size and measurement. The headline LMO cap typically sits in the 2–5% of Collateral Principal Amount range, but the measurement basis (cost, par, or fair market value) and the treatment of unfunded commitments are negotiated separately. Equity-form LMOs frequently carry a sub-cap inside the headline cap.
Source-of-funds permissions. Indentures differ on whether LMOs can be funded from Principal Proceeds, Interest Proceeds, or only from designated "Permitted Use" amounts in the subordinated portion of the Interest waterfall.
Reinvestment period status. Inside the reinvestment period, LMOs are one of several permitted purchase categories. Outside it, they remain permitted in most modern indentures but only subject to additional, deal-specific conditions — most commonly a prohibition on Principal Proceeds funding and a tighter senior OC "maintain or improve" requirement.
The most common purchase gate constraints, ranked
1. The LMO definition gate — designation, related-obligor link, loss-mitigation purpose. The single most binding constraint, and the one that fails most often. To qualify as an LMO at all, the candidate investment must satisfy a three-part definitional test: it is acquired in respect of an obligor — or a related obligor — that already underlies a Defaulted Obligation, Credit Risk Obligation, or other distressed position held by the CLO; its purpose is to mitigate a potential or actual loss on that existing position rather than to take fresh exposure; and the manager designates the investment as an LMO at the time of acquisition. The designation is typically irrevocable. Get it wrong at acquisition and the asset is treated under general Collateral Obligation rules, which usually means it fails eligibility outright.
2. Aggregate LMO investment cap. Modern US BSL indentures cap aggregate LMO holdings at a percentage of the Collateral Principal Amount — most commonly in the 2–5% range. The measurement methodology varies (cost basis is the most common, but par value and fair market value also appear), and unfunded commitments are sometimes counted toward the cap and sometimes not. The cap is typically tested both immediately before and immediately after the proposed purchase.
3. Source-of-funds restriction. The funding source is constrained by the waterfall mechanics. Three patterns dominate: Interest Proceeds funding via a specific subordinated waterfall step, sometimes capped per period; Principal Proceeds funding subject to an "LMO Principal Proceeds" sub-cap; and a hybrid permitting both with manager discretion. Outside the reinvestment period, the Principal Proceeds route is frequently closed entirely, leaving Interest Proceeds as the only permitted source.
4. Coverage Test "maintain or improve" gate. Even when the definitional and cap gates are clear, the manager typically has to confirm either that the OC and IC tests are satisfied immediately after the purchase, or — if any test was already failing — that the trade does not make any failing test worse. Because LMOs are usually carried at zero (equity form) or at a haircut value for OC numerator purposes, adding an LMO can mechanically pressure the senior OC test even when the trade is economically defensive. This is the gate that most often forces a trade to be downsized rather than refused.
5. Equity sub-cap inside the LMO bucket. Where the LMO is or includes an equity holding — the typical outcome of a debt-for-equity restructuring — an equity sub-cap inside the headline LMO cap usually applies, and is tested separately. The carrying-value treatment of equity-form LMOs — typically zero for OC purposes from inception — interacts directly with the coverage-test gate above.
6. Post-reinvestment period conditions. After the reinvestment period ends, LMO purchases remain permitted in most modern indentures but are gated by additional conditions: funding restricted to Interest Proceeds; a tighter "maintain or improve" requirement on the senior OC test; and a manager certification that the purchase is necessary to mitigate loss on the related existing position. This is one of the more bespoke areas of the indenture and where post-2022 vintages have tightened most visibly.
7. Manager certification and trustee notification. Procedural rather than substantive, but binding in practice. The manager is typically required to deliver a certificate to the trustee identifying the related existing position, confirming the LMO designation, certifying cap and coverage-test compliance, and stating the loss-mitigation rationale. The certificate must be in place before the purchase is reflected on the trustee's records — a constraint that affects timing even when the substantive gates are all clear.
Why generic AI gets this wrong
The most common failure mode is defined-term scope confusion. Generic models conflate LMO purchase gates with the eligibility criteria for ordinary Collateral Obligations, returning answers that cite WARF, WAL, diversity score, and CCC bucket tests as the binding constraints. They are not. Those tests run on the Collateral Obligation pool, and LMOs are typically carved out of that pool for eligibility and concentration purposes precisely because most LMOs would never clear them. The correct gate chain is the LMO-specific sequence above. The error is compounded by vintage: an older indenture with no LMO regime forces these trades through "equity security" or "workout loan" provisions with materially different gates, and a model trained on a mixed-vintage corpus blends the two without flagging it. Semeris extracts the LMO purchase gate chain — definition, cap, source of funds, coverage-test effect, equity sub-cap, post-reinvestment conditions, and certification requirements — as a discrete set of datapoints, separated from the general Collateral Obligation eligibility framework.
Semeris coverage
| Field | Value |
|---|---|
| US CLO deals indexed | 2,000+ |
| EU CLO deals indexed | 893 |
| Document extraction accuracy | 96% |
| Analyst verification | 100% (every indexed deal human-verified) |
| Relevant platform feature | Checklists — encode the LMO purchase-gate sequence as a reusable cross-deal review |
Related questions
- How is the LMO investment cap calculated, and what happens when it is breached?
- What manager certifications are required to designate a credit as an LMO at acquisition?
- Are LMOs subject to the standard Collateral Obligation concentration limits, or are they carved out?
Expert attribution
| Field | Value |
|---|---|
| Author | Tamas Trautmann, Semeris |
| Entity | Semeris — CLO Document Analysis |
| Last updated | 2026-07-28 |
| Data sources | Semeris internal database: document extraction accuracy (96%), analyst verification (100%). |
| Coverage | US & EU CLO markets — BSL CLOs, indentures, offering documents |
