What Is an Irrevocable Undertaking?
An irrevocable undertaking (IU) is a legally binding commitment from a shareholder to vote in favour of a proposed transaction (in a merger or scheme of arrangement) or to accept a tender offer. The undertaking is “irrevocable” because the shareholder cannot withdraw it — they are contractually locked in to supporting the deal regardless of subsequent events, subject to limited exceptions.
Irrevocable undertakings are a standard feature of public M&A in the UK, Australia, Hong Kong, Singapore, and other markets that follow the UK takeover tradition. They provide the acquirer with deal certainty before the transaction is announced, ensuring that a critical mass of shareholders has committed to support the deal.
Types of Irrevocable Undertakings
Hard Irrevocables
A hard irrevocable cannot be withdrawn under any circumstances — the shareholder is bound even if a competing bid emerges at a higher price. Hard irrevocables provide maximum deal certainty but may face legal challenges if they prevent shareholders from accepting a clearly superior offer.
Semi-Hard Irrevocables
A semi-hard irrevocable allows withdrawal only if a competing offer exceeds the original offer by a specified percentage (e.g., 10% or more). This provides the acquirer with protection against modest competitive bids while preserving the shareholder’s ability to accept a significantly superior offer.
Soft Irrevocables (Letters of Intent)
A soft irrevocable can be withdrawn if any competing offer emerges. These provide limited deal certainty and are functionally closer to a non-binding letter of support.
| Type | Withdrawal Permitted | Deal Certainty |
|---|---|---|
| Hard | Never | Highest |
| Semi-hard | Only if competing bid exceeds threshold | High |
| Soft | If any competing bid emerges | Moderate |
Who Provides Irrevocable Undertakings?
Directors and Management
Target company directors who own shares are typically the first to provide IUs. Their commitment signals board support and is disclosed in the offer announcement. Director IUs may also include undertakings to recommend the offer and not to solicit competing proposals.
Major Shareholders
Institutional investors, founders, family shareholders, and strategic investors who hold significant stakes are approached for IUs during the pre-announcement phase. Securing IUs from shareholders representing 30-50% of the target’s shares substantially increases deal certainty.
The Pre-Announcement Process
- Identify key shareholders — map the shareholder register to identify holders of meaningful positions
- Approach under NDA — contact shareholders confidentially, disclose the proposed terms, and request an IU
- Negotiate terms — agree on the form (hard vs. semi-hard), scope, and any conditions
- Execute before announcement — IUs are signed before the public announcement, and the aggregate IU level is disclosed at announcement
Legal Considerations
Enforceability
IUs are contracts and are enforceable under contract law. However, enforcement can be impractical — by the time a shareholder breach is detected and litigated, the offer may have lapsed. Practical enforcement often relies on:
- Reputational consequences for the breaching shareholder
- Damages claims for losses caused by the breach
- The shareholder’s depositary or broker being instructed to accept/vote automatically
Regulatory Treatment
The UK Takeover Code requires disclosure of all irrevocable undertakings in the offer announcement, including the identity of each shareholder, the number of shares committed, and the terms of the undertaking. Similar disclosure requirements exist in Hong Kong, Australia, and Singapore.
Concert Party Risk
Acquirers must be cautious that the process of obtaining IUs does not create a “concert party” with the committing shareholders, which could trigger mandatory offer obligations if the aggregate holding exceeds the takeover threshold.
APAC Context
Australia — irrevocable undertakings are a standard feature of Australian public M&A, particularly in schemes of arrangement. The Takeovers Panel has provided guidance on the acceptability of different IU structures, and pre-announcement IUs covering 30-50% of the target’s shares are common in scheme transactions.
Hong Kong — the SFC Takeovers Code requires disclosure of irrevocable commitments and letters of intent from shareholders. The Code distinguishes between irrevocable commitments (binding, disclosed in the announcement) and letters of intent (non-binding, also disclosed but carrying less weight).
Singapore — the Singapore Code on Take-overs and Mergers requires similar disclosure. Irrevocable undertakings are particularly important in Singapore where major shareholders (often family groups or sovereign wealth funds) hold concentrated positions.
“Irrevocable undertakings are the currency of deal certainty in APAC public M&A,” notes Daniel Bae, founder of Amafi. “Securing hard irrevocables from key shareholders before announcement can be the difference between a successful transaction and a failed bid.”
Planning public M&A transactions across Asia Pacific? Amafi helps companies and investors build deal certainty through strategic shareholder engagement. Learn more.