How does fund size (AUM) differentially impact the performance and management flexibility of a Large Cap Fund compared to a Small Cap Fund?

[ A ]A large AUM is illegal for Large Cap funds, but mandatory for all Small Cap funds.

[ B ]A large AUM is an advantage for Large Cap funds due to high underlying stock liquidity and economies of scale, whereas a very large AUM can hinder Small Cap funds due to limited liquidity and market-impact costs in smaller stocks.[ CORRECT ]

[ C ]Fund size has zero impact on portfolio construction or liquidity across all mutual fund categories.

[ D ]Small Cap funds with large AUM are forced by SEBI to invest 100% of their assets in US Government Treasury bonds.

Takeaway

Option B is correct: A large AUM is an advantage for Large Cap funds due to high underlying stock liquidity and economies of scale, whereas a very large AUM can hinder Small Cap funds due to limited liquidity and market-impact costs in smaller stocks.

Derivation

Fund size must be evaluated in the context of the underlying investment universe: In Large Cap funds, the top 100 stocks have massive trading volumes, allowing large funds (Rs. 30,000+ crore) to achieve superior sector diversification and lower expense ratios (economies of scale). In contrast, in Small Cap funds, underlying stocks have lower market capitalization and limited daily liquidity. A very large small-cap fund faces severe deployment bottlenecks, high impact costs when buying/selling, and may be forced to over-diversify into large caps. This tests fund size analysis. The common error is assuming bigger AUM is always better.

Why the others fail

A — A large AUM is illegal for Large Cap funds, but mandatory for all Small Cap funds.

Large AUM is completely legal for Large Cap funds, and small cap funds often cap inflows to protect performance.

C — Fund size has zero impact on portfolio construction or liquidity across all mutual fund categories.

Fund size significantly influences trading liquidity, stock selection breadth, and price impact costs across different capitalization categories.

D — Small Cap funds with large AUM are forced by SEBI to invest 100% of their assets in US Government Treasury bonds.

Domestic Small Cap funds are required to invest in domestic small cap equities, not foreign US Treasury bonds.