Waterfall Simulation

Distribution waterfalls are the most economically consequential -- and the most frequently misunderstood -- provisions in any LPA. They determine how every dollar of profit is split between LPs and the GP. FundAdmin AI's waterfall simulation translates the legal prose of your LPA into programmable logic, then executes it against concrete dollar amounts so you can see exactly who gets what, when, and under what conditions.

Waterfall analysis is one of FundAdmin AI's 59 skills (part of the Analysis & Reporting category) and integrates with both the 5-agent LPA review pipeline and the Obsidian vault's Risk Register dashboard.

What It Does

The waterfall simulator:

1. Parses the distribution waterfall provisions from the LPA
2. Classifies the waterfall structure (European vs American, with variations)
3. Translates the legal language into deterministic if/else/while logic (pseudocode)
4. Executes the logic against user-specified fund parameters (fund size, return multiple, preferred return rate)
5. Produces a dollar-amount execution trace showing the flow of capital through each tier
6. Analyzes edge cases -- what happens when distributions fall short, when the preferred return is never reached, or when clawback is triggered

The result is complete transparency into the economic mechanics of the fund. No more guessing what "100% GP catch-up until the GP has received 20% of aggregate profits" actually means in dollars.

Waterfall Tiers Explained

Most private equity distribution waterfalls follow a four-tier structure. The tiers are sequential -- distributions flow through each tier in order, and a tier must be fully satisfied before distributions move to the next.

Tier 1: Return of Capital

Distribution: 100% to LPs

All distributions first go to the LPs until they have received back their total contributed capital. This is the most fundamental LP protection -- you get your money back before the GP earns any carry.

Key details:

• "Contributed capital" typically means all capital called and not previously returned, including recycled capital in some structures
• Organizational expenses and management fees may or may not be included in the capital base (check the definition of "Contributed Capital" carefully)
• Some waterfalls include a return of expenses and fees as a separate sub-tier before return of invested capital

Tier 2: Preferred Return

Distribution: 100% to LPs (typically 8% compounded annually)

After LPs have received their capital back, all subsequent distributions go to the LPs until they have received a cumulative preferred return on their contributed capital. The preferred return (also called the "hurdle rate") is the minimum return the LPs must receive before the GP earns any carried interest.

Key details:

• The standard PE preferred return is 8% per annum, compounded annually
• Compounding method matters: annual compounding is standard; daily or continuous compounding is more LP-favorable; simple interest (no compounding) is more GP-favorable
• The preferred return accrues from the date capital is called, not the date of the first closing
• In some structures, the preferred return accrues only on unreturned capital (net of prior distributions), which is more GP-favorable

Tier 3: GP Catch-Up

Distribution: Typically 100% to GP (until the GP has received 20% of total profits)

The catch-up is the mechanism that brings the GP's share of total profits up to the carried interest percentage. After the LPs have received their capital back plus the preferred return, the GP receives 100% (or sometimes 80%) of subsequent distributions until the GP's cumulative distributions equal 20% of total profits distributed.

Key details:

• 100% catch-up: The GP receives all distributions in this tier until caught up. This is more GP-favorable because the GP receives large lump-sum distributions before the LP receives any more money.
• 80% catch-up: The GP receives 80% and the LP receives 20% of distributions in this tier. This is more LP-favorable because the LP continues receiving distributions during the catch-up period.
• The catch-up "target" is usually 20% of total cumulative profits (Tiers 2 + 3 combined), which means the GP's carry is calculated on all profits above return of capital.

Tier 4: Residual Split

Distribution: Typically 80% to LPs / 20% to GP

After the catch-up is complete, all remaining distributions are split according to the carry percentage -- typically 80/20 in favor of the LPs. This tier applies to all distributions above the point where the GP is fully caught up.

Key details:

• The 80/20 split is the standard for a 20% carry structure
• Some funds have tiered carry -- e.g., 20% carry up to 2x return, 25% carry above 2x, 30% carry above 3x
• The residual split continues for all remaining distributions through the life of the fund

European vs American Waterfall

The two most common waterfall structures differ fundamentally in when carry is calculated and distributed:

European (Whole-Fund) Waterfall

Calculate carry on the ENTIRE FUND after ALL investments are realized.

1. Return ALL contributed capital to LPs (across all deals)
2. Pay preferred return on ALL contributed capital
3. GP catch-up
4. 80/20 split on remaining

GP does not receive ANY carry until the entire fund has returned capital + preferred return.

LP advantage: The GP only earns carry if the fund as a whole exceeds the hurdle. Losses on bad deals reduce carry from good deals. This is the LP-preferred structure.

GP disadvantage: The GP may wait 8-12 years before receiving any carry, even if early deals are highly profitable.

American (Deal-by-Deal) Waterfall

Calculate carry on EACH DEAL independently as it is realized.

For each realization:
1. Return contributed capital for THAT DEAL to LPs
2. Pay preferred return on THAT DEAL's capital
3. GP catch-up on THAT DEAL
4. 80/20 split on THAT DEAL's remaining proceeds

GP receives carry on profitable deals EVEN IF other deals have losses.

GP advantage: The GP receives carry earlier and is not penalized for losses on other investments. A fund with five 3x winners and five total losses still pays carry on the winners.

LP disadvantage: The GP may receive carry on early winners that is never offset by later losses. This is why clawback provisions exist -- to recapture excess carry at the end of the fund.

Hybrid Structures

Many modern LPAs use hybrid approaches:

• European with interim distributions: Carry is calculated on a whole-fund basis, but the GP receives interim carry distributions subject to a true-up at liquidation.
• American with loss carry-forward: Deal-by-deal carry, but unrealized losses on other investments reduce the carry base for new realizations.
• American with escrow: Deal-by-deal carry, but 25-30% of GP carry distributions are held in escrow pending final fund liquidation.

The simulator identifies which structure the LPA uses and flags any deviations from the pure European or American model.

Edge Case Analysis

The simulator automatically analyzes three critical edge cases:

Edge Case 1: Distributions Less Than Contributed Capital

Scenario: The fund returns less than 1.0x -- LPs lose money.

Fund size: $100M contributed capital
Total distributions: $80M (0.8x return)

Tier 1 (Return of Capital):
  - LPs receive $80M (all available distributions)
  - LPs have NOT received full return of capital ($20M shortfall)

Tier 2-4: NEVER REACHED

Result:
  - LPs receive: $80M (loss of $20M)
  - GP receives: $0 carry
  - GP catch-up: $0
  - Preferred return unpaid: $8M+ (depending on timing)

What to watch for: Even in a loss scenario, verify that the GP does not receive any distributions. Some waterfalls have provisions for "return of GP capital" that could allow the GP to receive distributions before LPs are made whole.

Edge Case 2: Preferred Return Never Fully Reached

Scenario: The fund returns capital but does not generate enough profit to fully satisfy the preferred return.

Fund size: $100M contributed capital
Total distributions: $105M (1.05x return)
Preferred return (8% over 5 years, compounded): ~$46.9M

Tier 1 (Return of Capital):
  - LPs receive $100M (full return of capital)

Tier 2 (Preferred Return):
  - LPs receive $5M (remaining distributions)
  - Preferred return shortfall: ~$41.9M

Tier 3-4: NEVER REACHED

Result:
  - LPs receive: $105M (modest gain, but below hurdle)
  - GP receives: $0 carry

What to watch for: The preferred return must be fully satisfied before any carry is paid. A fund that returns 1.05x over 10 years has technically returned capital with a small gain, but the GP earns no carry because the cumulative preferred return was never met.

Edge Case 3: Clawback Trigger

Scenario (American waterfall): Early deals are profitable and carry is paid, but later deals lose money, resulting in excess carry paid to the GP.

Fund size: $100M
Deal 1 (Year 3): Invested $20M, returned $60M (3x)
  - Carry paid to GP on Deal 1: ~$6.4M

Deal 2 (Year 5): Invested $20M, returned $50M (2.5x)
  - Carry paid to GP on Deal 2: ~$4.4M

Deals 3-5 (Years 6-9): Invested $60M, returned $30M (0.5x -- losses)

Total: Invested $100M, returned $140M (1.4x)
Cumulative carry paid: $10.8M

Whole-fund carry calculation:
  - Total profit: $40M
  - Preferred return (8%, ~5yr avg): ~$34M
  - Profits above pref: ~$6M
  - 20% carry on profits above pref: ~$1.2M

CLAWBACK TRIGGERED: GP must return $10.8M - $1.2M = $9.6M

Result (if clawback enforced):
  - LPs receive: $140M fund distributions + $9.6M clawback = $149.6M
  - GP net carry: $1.2M

What to watch for: Clawback enforceability. If there is no escrow and the GP has already spent or distributed the carry to individuals, the clawback depends on personal guarantees. "Net of taxes" clawback provisions further reduce the amount recoverable.

Pseudocode Generation

The simulator translates the LPA's waterfall provisions into executable pseudocode. This makes the economic logic unambiguous and auditable.

Example: European Waterfall with 8% Pref, 100% Catch-Up, 80/20 Split

def distribute_european_waterfall(
    contributed_capital: float,
    total_distributions: float,
    pref_rate: float = 0.08,
    carry_pct: float = 0.20,
    catchup_pct: float = 1.00,  # 100% to GP during catch-up
    years: float = 5.0
):
    remaining = total_distributions
    lp_total = 0.0
    gp_total = 0.0

    # Tier 1: Return of Capital (100% to LPs)
    tier1 = min(remaining, contributed_capital)
    lp_total += tier1
    remaining -= tier1

    if remaining <= 0:
        return {"LP": lp_total, "GP": gp_total, "tiers_reached": 1}

    # Tier 2: Preferred Return (100% to LPs)
    pref_amount = contributed_capital * ((1 + pref_rate) ** years - 1)
    tier2 = min(remaining, pref_amount)
    lp_total += tier2
    remaining -= tier2

    if remaining <= 0:
        return {"LP": lp_total, "GP": gp_total, "tiers_reached": 2}

    # Tier 3: GP Catch-Up
    # GP receives catchup_pct of distributions until GP has
    # carry_pct of total profits (Tier 2 + Tier 3)
    total_profit_so_far = tier2  # profits = distributions above return of capital
    # Target: GP should have carry_pct / (1 - carry_pct) * pref_amount
    catchup_target = (carry_pct / (1 - carry_pct)) * pref_amount
    catchup_needed = catchup_target

    while remaining > 0 and catchup_needed > 0:
        gp_share = min(remaining * catchup_pct, catchup_needed)
        lp_share = min(remaining * (1 - catchup_pct), remaining - gp_share)
        gp_total += gp_share
        lp_total += lp_share
        remaining -= (gp_share + lp_share)
        catchup_needed -= gp_share

    if remaining <= 0:
        return {"LP": lp_total, "GP": gp_total, "tiers_reached": 3}

    # Tier 4: Residual Split (80/20)
    lp_total += remaining * (1 - carry_pct)
    gp_total += remaining * carry_pct
    remaining = 0

    return {"LP": lp_total, "GP": gp_total, "tiers_reached": 4}

This pseudocode is generated dynamically based on the actual LPA terms. If the LPA uses an 80% catch-up instead of 100%, the catchup_pct parameter changes. If the carry is tiered (20% up to 2x, 25% above), additional logic branches are added.

Dollar-Amount Execution Trace

Here is a complete execution trace for a $100M fund with a 1.5x return ($150M total distributions), using a European waterfall with 8% preferred return, 100% GP catch-up, and 80/20 residual split over a 5-year average hold period:

═══════════════════════════════════════════════════════════════════
WATERFALL EXECUTION TRACE
Fund Size: $100,000,000 | Total Distributions: $150,000,000
Structure: European | Pref: 8% compounded | Catch-Up: 100% GP
═══════════════════════════════════════════════════════════════════

TIER 1: Return of Capital
  Available:        $150,000,000
  To LPs:           $100,000,000  (100%)
  To GP:            $0
  Remaining:        $50,000,000
  ─────────────────────────────────────────────
  LP cumulative:    $100,000,000
  GP cumulative:    $0

TIER 2: Preferred Return (8% compounded, 5 years)
  Preferred amount: $46,932,808
  Available:        $50,000,000
  To LPs:           $46,932,808   (100%)
  To GP:            $0
  Remaining:        $3,067,192
  ─────────────────────────────────────────────
  LP cumulative:    $146,932,808
  GP cumulative:    $0
  Total profit:     $46,932,808

TIER 3: GP Catch-Up (100% to GP)
  Catch-up target:  $11,733,202   (20/80 * pref_amount)
  Available:        $3,067,192
  To LPs:           $0            (0%)
  To GP:            $3,067,192    (100%)
  Catch-up filled:  $3,067,192 of $11,733,202 (26.1%)
  Remaining:        $0
  ─────────────────────────────────────────────
  LP cumulative:    $146,932,808
  GP cumulative:    $3,067,192

TIER 4: Residual Split -- NOT REACHED

═══════════════════════════════════════════════════════════════════
FINAL DISTRIBUTION SUMMARY
═══════════════════════════════════════════════════════════════════
  LP total:         $146,932,808  (97.96% of distributions)
  GP total:         $3,067,192    (2.04% of distributions)

  LP return:        1.469x on contributed capital
  GP carry:         $3,067,192    (effective carry rate: 6.13%)

  NOTE: GP catch-up was NOT fully satisfied. The GP received only
  26.1% of its target catch-up amount. In a higher-return scenario
  (e.g., 2.0x), the GP would receive the full catch-up and the
  residual 80/20 split would activate.
═══════════════════════════════════════════════════════════════════

What This Trace Reveals

At a 1.5x return, the economics are heavily LP-favorable even with a 100% GP catch-up. The preferred return consumes nearly all of the profit ($46.9M of $50M), leaving only $3.1M for the GP catch-up. The GP never reaches Tier 4. The effective carry rate is 6.13% -- far below the contractual 20%.

This is why GPs push for American (deal-by-deal) waterfalls. In an American structure, carry is calculated on each profitable deal independently, and the GP can earn 20% carry on winners even if the fund as a whole only returns 1.5x.

How to Use

Run the waterfall simulation on any LPA document:

/fund smart-contract-sim path/to/lpa-document.pdf

The simulator will:

1. Extract the waterfall provisions from the LPA
2. Display the classified waterfall structure
3. Generate the pseudocode translation
4. Run the default execution trace ($100M fund, 1.5x return)
5. Run edge case analysis (sub-1x, just-above-pref, clawback trigger)
6. Output all results to the terminal and store them for the PDF report

Custom Parameters

You can specify custom fund parameters for the execution trace:

/fund smart-contract-sim path/to/lpa.pdf --fund-size 500000000 --return-multiple 2.0

This runs the trace on a $500M fund with a 2.0x return, showing how the waterfall distributes $1B in total proceeds.

Why This Matters

Waterfall provisions are dense legal prose that even experienced fund lawyers sometimes misinterpret. The economic difference between an 80% catch-up and a 100% catch-up, or between a European and American waterfall, can be millions of dollars on a large fund. The simulation gives you:

• Certainty: You know exactly what the waterfall does in dollars, not in abstract legal language.
• Comparison: Run the same fund parameters through two different LPAs to see which is more LP-favorable.
• Negotiation leverage: "Under your proposed waterfall, the GP receives $X at a 1.5x return. Under market-standard terms, the GP would receive $Y. The difference is $Z."
• Edge case awareness: You know what happens in loss scenarios before they happen.