Activist Investing in Investment Banking Explained

Shareholder activism has grown from a niche corner of the hedge fund world into one of the most consequential forces in corporate finance. In 2025, activists launched a record 255 campaigns globally, pushing companies to pursue mergers, spin off divisions, replace CEOs, return capital to shareholders, and overhaul their strategies. Roughly half of all activist campaigns in the second half of 2025 included an explicit M&A component, making activism directly relevant to the core advisory work of investment banks.

For aspiring bankers, understanding activism is important for several reasons. Investment banks advise on both sides of activist situations: helping companies defend against campaigns and helping activist funds build their investment theses and push for change. Activism-related advisory is a growing revenue stream at firms like Goldman Sachs, J.P. Morgan, Morgan Stanley, and boutiques with dedicated shareholder advisory practices. And activist situations frequently come up in interviews, particularly when discussing recent deals in the news or current market and industry trends.

This article explains how activist investing works, what tactics both sides use, how investment banks fit into the picture, and how this topic shows up in banking interviews.

Activist Investor

A shareholder (typically a hedge fund or investment firm) that acquires a significant stake in a public company and then uses that ownership position to push for changes intended to increase shareholder value. Activist campaigns can target strategy, operations, capital allocation, governance, or management, and may escalate to proxy fights for board seats if the company resists.

Activist investors differ from passive shareholders in one fundamental way: they do not simply buy shares and wait. They acquire stakes with a specific thesis about what is wrong with the company and what changes would unlock value. Then they actively engage management and the board to push for those changes.

The typical activist playbook involves several stages. First, the fund identifies an undervalued company where specific, identifiable actions could close the gap between current market price and intrinsic value. The fund quietly accumulates shares up to the SEC disclosure threshold (currently 5% of outstanding shares, which triggers a Schedule 13D filing). Once the position is built, the activist engages management privately, presenting their analysis and proposed changes. If private engagement fails, the activist escalates publicly, often through open letters, media campaigns, and ultimately proxy fights for board representation.

The most prominent activist funds include Elliott Management (founded by Paul Singer, managing over $70 billion), Trian Partners (founded by Nelson Peltz), Starboard Value, Pershing Square (Bill Ackman), Third Point (Dan Loeb), Ancora Advisors, and Mantle Ridge. These firms have reshaped major public companies across every sector.

Activist campaigns generally fall into several categories, and understanding these helps you see why investment banks are involved.

Strategic Changes and M&A

The most impactful activist campaigns push for transformational strategic moves. This includes demanding that companies pursue acquisitions, sell themselves, divest non-core business units, or execute spin-offs and carve-outs. When activists push for M&A, investment banks are needed on both sides: the company needs advisors to evaluate the proposal, and the activist may retain bankers to build its case.

Operational Improvements

Some activists focus on margin expansion and operational efficiency rather than structural changes. They argue that management is spending too much, that cost structures are bloated, or that the company's margins lag behind peers. These campaigns are data-intensive and require detailed benchmarking analysis.

Capital Allocation

Activists frequently push companies to return more capital to shareholders through share buybacks or special dividends, arguing that the company is hoarding cash or investing in low-return projects. They may also challenge excessive executive compensation or poorly structured incentive plans.

Governance and Board Composition

Many campaigns target the quality and independence of the board. Activists argue that directors are too cozy with management, lack relevant expertise, or have served too long. Winning board seats gives activists a direct voice in strategic decisions and access to information that outside shareholders cannot obtain.

ESG and Social Activism

A growing category involves environmental, social, and governance (ESG) activism, where investors push for climate commitments, workforce diversity, or governance reforms. While ESG-focused activism generates less M&A advisory work, it has become a significant part of the landscape and is increasingly supported by large institutional investors.

When private engagement fails, the activist's primary weapon is the proxy fight: a battle for shareholder votes to elect the activist's nominees to the company's board of directors.

Proxy Fight

A campaign in which a dissident shareholder (typically an activist investor) solicits votes from other shareholders to elect alternative directors to the company's board, replace existing directors, or approve specific corporate actions. Both the company and the activist distribute proxy materials making their case, and the outcome is determined by a shareholder vote at the annual or special meeting.

The economics of proxy fights are significant. A full-scale proxy contest at a large company can cost $10 million to $50 million or more in legal fees, banker advisory fees, proxy solicitation, public relations, and printing costs. This is why most campaigns settle before reaching a vote. In 2025, the majority of activist campaigns that sought board seats resulted in negotiated settlements rather than contested elections.

When a company becomes an activist target, its board and management team deploy a range of defense strategies. This is where investment banking advisory becomes critical.

Poison Pills (Shareholder Rights Plans)

Poison Pill (Shareholder Rights Plan)

A defensive mechanism adopted by a company's board that makes a hostile acquisition prohibitively expensive. When triggered (typically when any single shareholder acquires more than 10-20% of outstanding shares), all other shareholders receive the right to purchase additional shares at a steep discount, massively diluting the activist's or acquirer's stake. Poison pills are designed to force negotiation rather than unilateral accumulation.

Poison pills do not permanently block activists, but they buy time by preventing rapid share accumulation. The board can then evaluate the situation, engage advisors, and formulate a strategic response. Modern poison pills are typically adopted for limited durations (one to three years) and have lower trigger thresholds than those used in the 1980s and 1990s.

Staggered Boards

A staggered (or classified) board divides directors into three classes, with only one class standing for election each year. This means an activist cannot replace a majority of the board in a single proxy fight; it takes at least two election cycles. Staggered boards have become less common at large-cap companies due to institutional investor pressure for annual elections, but they remain a powerful structural defense where they exist.

Other Defense Mechanisms

Companies targeted by activists deploy additional tactics:

Investment banks play advisory roles on both sides of activist situations, and understanding these roles helps you see why activism is relevant to your banking career.

Defense Advisory

When a company is targeted (or anticipates being targeted), it hires investment banks to provide activism defense advisory. The advisory work includes:

Major banks including Goldman Sachs, J.P. Morgan, and Morgan Stanley have dedicated shareholder advisory groups. Boutique firms like Evercore, Lazard, and PJT Partners also have significant activism defense practices.

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Activist-Side Advisory

On the other side, some banks and advisory firms work with activists to:

Working with activists is more common at boutique advisory firms and independent advisors, though large banks occasionally take activist-side mandates when there is no conflict with existing client relationships.

Fee Structures

Activism advisory fees are typically structured as retainer-based engagements rather than success fees. A company on defense might pay $1 million to $5 million or more in annual advisory retainers, with additional fees if the situation escalates to a proxy fight or triggers M&A activity. If the activist situation leads to a sale or merger, the advisory fees shift to standard M&A transaction-based compensation.

The activism environment heading into 2026 is characterized by several notable trends.

Record campaign volume. The 255 campaigns launched in 2025 set a new high-water mark, driven by favorable equity market conditions and a growing number of first-time and emerging activists targeting smaller-cap companies.

M&A-driven activism. With roughly half of campaigns in late 2025 including an M&A component, activism and traditional M&A advisory are increasingly intertwined. Activists are pushing companies to sell themselves, pursue acquisitions, or execute divestitures at a higher rate than in previous cycles.

Record CEO exits. Activist pressure drove a record number of CEO departures in 2025, reflecting the growing willingness of boards to make leadership changes in response to shareholder pressure.

Evolving tactics. Campaigns have moved beyond traditional letters and proxy statements. Elliott Management's use of podcasts and YouTube during its Phillips 66 campaign illustrates how activists are adopting digital media to reach retail shareholders and shape public narratives.

Regulatory uncertainty. The SEC's evolving stance on proxy advisory firms (ISS and Glass Lewis) could reshape the dynamics of proxy fights in 2026. Potential increased scrutiny of these firms may reduce their influence on shareholder voting, which would benefit incumbent boards in contested situations.

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Activist investing is a rich topic for banking interviews because it sits at the intersection of M&A, corporate governance, valuation, and market awareness.

Activist investing has become a permanent and growing feature of the corporate finance landscape. For investment bankers, activism creates advisory opportunities on both sides of the table, from helping companies defend their strategic plans to helping activists build the financial case for change. The intersection of activism and M&A means that bankers in coverage groups, M&A teams, and dedicated shareholder advisory practices all encounter these situations regularly.

Understanding how activist campaigns work, what defense tactics companies deploy, and how proxy fights unfold gives you a more complete picture of the advisory role investment banks play. It also prepares you for interview questions that go beyond standard valuation and modeling topics into the strategic and governance dimensions of corporate finance. As activism continues to set records and evolve in its tactics and targets, this is a topic that will only become more central to the work investment bankers do.