Platt Investment Counsel, LLC — Quarterly 13F Portfolio Report

Platt Investment Counsel, LLC's disclosed holdings carry a Herfindahl concentration index of 0.168 — mathematically equivalent to about 6 equally-sized positions, well below its 13 actual disclosed holdings. That gap points to a strategy built around a small core of high-conviction bets rather than broad diversification.

Position sizes are fairly uniform across the portfolio (a coefficient of variation of 1.13), suggesting a disciplined, rules-based approach to how much capital goes into each idea.

Recent activity leans toward adding more aggressively to already-large existing positions than to newly initiated ones (a 3.0 percentage-point tilt) — a pattern consistent with a momentum-following approach.

Sector classification currently covers about 1% of this portfolio's disclosed value; the remainder includes holdings (e.g. unmapped tickers, options, or other security types) not yet covered by our sector mapping.