# How to manage a sidecar investment vehicle

Understand what a sidecar investment vehicle is, how to use one to pursue high-conviction deals, and what it takes to manage its lifecycle, economics, and compliance.

## What is a sidecar investment vehicle?

A sidecar investment vehicle is a specialized [fund structure](/content/uk/en/learn/private-funds/structures/index.html) that allows a fund’s existing investors to participate in a specific investment deal alongside the main fund. This structure is typically a [special purpose vehicle (SPV)](/content/uk/en/learn/private-funds/structures/spv/index.html) that is managed by the fund's [general partner (GP)](/content/uk/en/learn/private-funds/structures/general-partner/index.html). The GP uses the sidecar to pool capital from their [limited partners (LP)](/content/uk/en/learn/private-funds/structures/limited-partner/index.html) for a single, targeted investment.

Think of it like a motorcycle with a sidecar attached. The GP is the driver, navigating the investment landscape based on the expertise required to [manage a private equity (PE) fund](/content/uk/en/learn/private-funds/management/index.html) successfully. The LPs in the main fund are passengers on the motorcycle, and the sidecar offers a select group of those LPs a chance to ride alongside the GP for a specific, targeted journey—a single investment opportunity.

The GP first identifies a compelling deal—often formalizing the valuation, due diligence, and rationale in an [investment memo](/content/uk/en/learn/private-funds/management/portfolio-management/investment-memo/index.html)—and then creates the sidecar to gather the necessary capital to fund it. This allows the GP to make a larger investment in the target company than they could with the main fund alone. At the same time, it gives interested LPs more exposure to a deal that the GP has high conviction in.

### How sidecars differ from funds and SPVs

While a sidecar is a type of SPV, its purpose and investor base make it distinct. To fully grasp the concept, it's helpful to see how a sidecar compares to other common investment structures. The key distinction is the sidecar's direct relationship with a main fund and its existing LPs.

A main fund is designed to invest in a portfolio of multiple companies, spreading risk across different assets within their investment portfolios according to a broad [investment thesis](/content/uk/en/learn/private-funds/management/portfolio-management/investment-thesis/index.html) developed during [portfolio construction](/content/uk/en/learn/private-funds/management/portfolio-management/portfolio-construction/index.html). In contrast, a standard SPV is a standalone vehicle that can be used by any group of [accredited investors](/content/uk/en/learn/private-funds/regulations/accredited-investors/index.html), like an [angel syndicate](/content/uk/en/learn/private-funds/structures/spv/angel-syndicates/index.html), to invest in a single company, and it doesn't require a preexisting main fund.

A sidecar vehicle sits between these two. It is also a single-asset vehicle, but sidecar investors are primarily the existing LPs from the GP's main fund, creating a focused opportunity for a group that already has a relationship with the [fund manager](/content/uk/en/learn/private-funds/structures/fund-manager/index.html).

|     |     |     |
| --- | --- | --- |
| **Structure** | **Purpose** | **Typical investor base** |
| **Main fund** | Invests in a portfolio of multiple companies according to a broad investment thesis. | A diverse group of LPs, including [institutional investors](/content/uk/en/learn/private-funds/structures/institutional-investors/index.html), high-net-worth individuals, and the occasional [angel investor](/content/uk/en/learn/startups/fundraising/investors/angel-investors/index.html). |
| **Sidecar vehicle** | Invests in a single, specific company alongside the main fund. | Primarily existing LPs from the main fund. |
| **Standard SPV** | Invests in a single, specific company. | Can be any group of accredited investors, not necessarily tied to a main fund. |

## Why GPs use sidecar vehicles

GPs use sidecar vehicles for several strategic purposes, such as exceeding fund concentration limits or making off-thesis investments. One of the most common drivers is the need to execute [follow-on investments](/content/uk/en/learn/private-funds/management/portfolio-management/follow-on-investment/index.html) to support existing p [ortfolio companies](/content/uk/en/learn/private-funds/structures/portfolio-company/index.html).

As the venture capital market has shifted, the need for this kind of [bridge financing](/content/uk/en/learn/startups/fundraising/bridge-rounds/index.html) has become more frequent, partly because the [average holding period](https://corpgov.law.harvard.edu/2025/01/24/private-equity-2024-review-and-2025-outlook/) for portfolio companies has increased, requiring more capital over a longer duration. GPs typically use sidecar vehicles in a few common scenarios:

- **To exceed concentration limits**: The governing fund documents, like the [limited partnership agreement](/content/uk/en/learn/private-funds/structures/limited-partner/lpa/index.html), often include rules that restrict how much capital can be put into a single company.
- **To make off-thesis investments**: Sometimes a GP finds a compelling sidecar opportunity that falls outside of the fund’s investment thesis.
- **To execute follow-on investments**: A sidecar allows LPs who are excited about a company's progress to double down on a winner and provide the needed startup funding for its next stage of growth.

### Common sidecar structures: Overage, annex, and top-up funds

Sidecars can be structured in several ways depending on their specific purpose. Here are a few common types of sidecar funds:

- **Overage funds**: Used to invest the amount of a deal that is "over" the main fund's concentration limit.
- **Annex funds**: Raised after the main fund's official investment period has ended to provide follow-on capital.
- **Top-up funds**: Raised during the main fund's investment period to take advantage of new market opportunities.

## How to manage the sidecar vehicle lifecycle

The administrative process for managing an SPV has historically been complex and manual. The lifecycle of a sidecar can be broken down into three main stages:

### Step 1: Forming the legal entity

Creating a new legal entity, usually a Delaware LLC or limited partnership. This process involves drafting operating agreements, managing state filings, and obtaining a federal tax ID number.

### Step 2: Onboarding investors and closing capital

The next operational challenge is [bringing LPs into the sidecar](/content/uk/en/learn/private-funds/management/fund-administration/investor-onboarding/index.html) and collecting their capital commitments through a [capital call](/content/uk/en/learn/private-funds/management/capital-calls/index.html).

### Step 3: Administering the investment and reporting to LPs

After the investment is made, ongoing management responsibilities include tracking the [investment fund performance](/content/uk/en/learn/private-funds/management/fund-performance/index.html) and preparing quarterly financial reports.

## How are sidecar economics structured?

Sidecar investments typically offer more favorable terms, which is a key reason why LPs find them attractive. Sidecar vehicles usually waive or reduce [management fees](/content/uk/en/learn/private-funds/management/management-fees/index.html) and [carried interest](/content/uk/en/learn/private-funds/management/carried-interest/index.html).

## How to manage conflicts and compliance

Managing conflicts of interest with sidecar arrangements is crucial. Best practices include:

- **Offer opportunities on a pro-rata basis**: Ensuring fairness as opportunities are typically offered to existing LPs.
- **Maintain clear allocation policies**: Outlining the rules for deciding which deals go into which vehicle.
- **Disclose all terms transparently**: Ensuring all parties involved understand what they are agreeing to.

## Integrating sidecars into your fund strategy

Sidecars are more than just one-off fixes for portfolio constraints; they can become a core part of your firm's [investment strategy](/content/uk/en/learn/private-funds/private-equity/strategies/index.html). Integrating sidecars and other SPVs can facilitate bespoke investments.

## Frequently asked questions about sidecar investments

### What is the difference between a sidecar and co-investment?

A sidecar is a specific type of [co-investment](/content/uk/en/learn/private-funds/structures/co-investment/index.html) vehicle.

### What are the tax implications of a sidecar investment?

When structured as a pass-through entity like an LLC or LP, the sidecar itself is not taxed. Investors receive a Schedule K-1 and are responsible for reporting their income.

### Can a sidecar vehicle invest in more than one company?

Some structures like overage or top-up funds can be blind-pool vehicles, designed to invest in multiple opportunities.