Level III Core · Overview of Equity Portfolio Management

Active Equity Investing: Styles and Approaches

Updated 9 October 2026 · Fact-checked

Active equity investing tries to beat a benchmark through stock selection or weighting decisions. Main styles are value, growth, GARP, quantitative and factor-based. To solve questions, identify the manager's process, match it to the style, check style drift and active share, and tie the choice to the client's needs.

Understand Active Equity Investing: Styles and Approaches

An active equity manager holds a portfolio that differs from the benchmark, hoping to earn excess return after fees. The difference can come from stock selection, sector or country weights, or factor tilts. A passive manager simply replicates the index.

The main styles are these. Value managers buy stocks that look cheap relative to fundamentals, using low P/E, low P/B or high dividend yield. Sub-types are low-multiple, contrarian (out-of-favour companies) and yield-oriented. Growth managers buy firms with above-average earnings or revenue growth and accept higher multiples. Sub-types are consistent growth and earnings-momentum. GARP (growth at a reasonable price) sits between the two and often uses the PEG ratio. Quantitative managers use rules-based models with many stocks. Factor-based investing tilts to rewarded exposures such as value, size, momentum, quality and low volatility.

Process matters too. Bottom-up managers start with company analysis and let sector weights be a result. Top-down managers start with macro views on countries, sectors or themes, then choose stocks. Fundamental managers typically use judgement and in-depth research on fewer stocks. Quantitative managers use systematic models across many stocks, often with lower research cost per stock.

Style drift happens when a manager's portfolio moves away from the style they were hired to deliver. A value manager that buys growth stocks to chase returns is drifting. This hurts the client because it breaks the asset-allocation plan and can cause overlap or gaps between managers. A style box (value/blend/growth by large/mid/small) lets you see where holdings sit and spot drift over time.

Active share measures how different holdings are from the benchmark weights. Active risk (tracking risk) measures the volatility of returns relative to the benchmark. Read the two together:

High active share with low tracking error suggests diversified stock picking.
High active share with high tracking error suggests concentrated stock picks.
Low active share with low tracking error suggests closet indexing.
Low active share with high tracking error suggests factor or sector bets (large exposures to a few factors or sectors, but holdings close to the benchmark).

Always link the style to the client's objectives, risk tolerance and fee budget.

Key rules to remember

Active share: Active share = ½ × Σ |w(portfolio,i) − w(benchmark,i)|; Sum over all securities. A value of 0% is a pure index copy; 100% means no overlap with the benchmark.
Active return: Active return = Portfolio return − Benchmark return; Also called excess return versus the benchmark.
Active risk (tracking error): Active risk = standard deviation of (Rp − Rb); Measured over time using the active returns.
Information ratio: IR = Average active return ÷ Active risk; Return per unit of active risk. Higher is better.
PEG ratio: PEG = P/E ÷ expected earnings growth rate (in % points); Used by GARP managers. A lower PEG suggests growth is cheaper.

How to solve Active Equity Investing: Styles and Approaches questions

Use this method for any vignette or essay on equity styles and approaches.

1Read the command word first (identify, justify, calculate, recommend). Answer only what it asks.
2Find the evidence of style: valuation multiples, growth rates, turnover, number of holdings, how stocks are chosen.
3Classify the process as bottom-up or top-down and fundamental or quantitative.
4Check for style drift by comparing current holdings with the mandated style or style box.
5If numbers are given, calculate active share, active return, tracking error or information ratio and show the working.
6Link your conclusion to the client's objectives, risk tolerance, cost sensitivity and other managers in the portfolio.
7Write the answer in the fewest words that cover the points: state the conclusion, then one reason from the vignette.

Quickest way: Label, test, tie to client

When to use it: Use for multiple-choice questions where you must pick a style, a drift conclusion or an active-share reading quickly.

Label the style from the clue: low multiples means value, high growth means growth, growth with a PEG screen means GARP, model-driven means quantitative.
Test against the mandate: does the portfolio still match? If not, it is style drift.
For active share, remember high means few overlaps with the benchmark; for tracking error, high means volatile relative returns.
Eliminate options that confuse active share with active risk.
Pick the option that fits the client's stated need.

Common mistakes in Active Equity Investing: Styles and Approaches

Confusing active share with tracking error.
Both measure difference from the benchmark.
Fix: Active share is about holdings weights. Tracking error is about volatility of return differences.
Calling any manager who holds growth stocks a growth manager.
Students look at one holding, not the process.
Fix: Judge the style from the whole portfolio and the selection discipline, not one stock.
Treating style drift as always bad performance.
Drift often follows strong returns.
Fix: Drift is a mismatch with the mandate, even when returns are good. The problem is the broken allocation and unmanaged risk.
Assuming value always means low risk.
Cheap seems safe.
Fix: Cheap stocks can be cheap for a reason (value traps). Say that value carries its own risks.
Mixing up top-down and bottom-up.
Both can end with stock picks.
Fix: Top-down starts with macro and sector views. Bottom-up starts with the company.
Giving a recommendation with no link to the client.
Candidates describe the style but forget the IPS.
Fix: End each answer with a reason tied to the client's objective, risk or constraint.

Worked examples

Example 1

A three-stock benchmark has weights of 50%, 30% and 20% in stocks A, B and C. A portfolio holds 40%, 40% and 20%. Calculate the active share.

Show the solution

Find absolute weight differences: |40−50| = 10, |40−30| = 10, |20−20| = 0.
Add them: 10 + 10 + 0 = 20.
Multiply by ½: 0.5 × 20 = 10.

Answer: Active share is 10%, which is low and suggests the portfolio is close to the benchmark.

Example 2

A mandate requires a large-cap value manager. Over two years the manager sells stocks with P/E below 12 and buys small-cap stocks with earnings growth above 25% and P/E above 30. Returns have beaten the benchmark. State whether style drift has occurred and what the client should do.

Show the solution

Identify the mandate: large-cap value.
Compare current holdings: small-cap, high growth, high P/E, which is a growth, small-cap profile.
Conclude the portfolio has moved away from the mandate, so style drift has occurred.
Note that good returns do not remove the drift; the client's asset allocation and mix of managers are now distorted.
Recommend the client discuss with the manager, require a return to the mandate, and consider replacing the manager if drift continues.

Answer: Yes, style drift has occurred: the manager moved from large-cap value to small-cap growth. The client should require the manager to restore the mandated style or consider replacing them, because the drift upsets the planned allocation even though returns were strong.

Exam tips

Always give a reason from the vignette, such as a P/E figure or number of holdings, not just the label.
Show the active share working line by line; a correct number alone also earns credit, but the working protects you if you slip.
For a recommendation, say how the style fits the client's risk tolerance and other managers.
Know the differences: active share is holdings-based, tracking error is return-based.
Respond to only the number of items asked, in the order given.

Active Equity Investing: Styles and Approaches: frequently asked questions

What is the difference between value and growth investing?

Value managers look for stocks priced low relative to fundamentals such as earnings or book value. Growth managers buy firms with above-average expected growth and accept higher multiples. GARP blends the two.

What is style drift in an equity portfolio?

It is a move by a manager away from the style they were hired to deliver. It matters because it disturbs the client's allocation and can create overlaps or gaps between managers.

What is the difference between bottom-up and top-down investing?

Bottom-up starts with analysis of individual companies. Top-down starts with macro, country or sector views and then picks stocks within them.

What does active share tell you?

It shows how much the portfolio's holdings differ from the benchmark. A higher value means more of the portfolio differs from the index. It does not measure the volatility of relative returns, which is active risk.