undamentalytics Newsletter

Nebreda Julian: insider trades

Chief executive, Officer, Director at 2 companies we cover. 6 open-market purchases and 1 sale not made under a pre-set plan, reported from September 4, 2019 to March 17, 2025.

Would copying Nebreda Julian’s purchases have beaten the S&P 500?

Too few purchases to judge. Only 6 purchases have 12 months of prices after the report; we judge insiders once they have 20. The figures below can swing a long way on a handful of trades. Buying each purchase the day after it was reported, an equal amount each, and holding it 12 months or until they reported a sale would have turned $10,000 on March 23, 2020 into $44,969 by November 2, 2026, +25.6% a year. The copy held shares only 69% of the time, so the fair comparison is the S&P 500 on those same days with Treasury bills otherwise: $25,706, +15.4% a year (the S&P 500 held throughout made $37,099, +22.0% a year). Beta against the index was 1.54. Twelve months after each report, the average purchase was +59.0% against the S&P 500 (median +47.7%), and 83% beat it. Measured from the trade date, the insider’s own timing, the average was +78.2%. After their sales, the shares moved +0.3% against the index over 12 months on average (a negative figure means selling was the right call); 0% trailed it.

With 296 insiders tested, some will look skilled or unskilled by chance alone: when we replaced each insider’s stocks with random companies bought on the same days, about 5.7 cleared the bar ahead and 23.3 behind. One record on its own proves little.

$0$25.0k$50.0k$75.0k 2020202120222023202420252026 $45.0k$37.1k$25.7k
Copying Nebreda JulianS&P 500, same days investedS&P 500, held throughout $10,000 copying Nebreda Julian’s open-market purchases from March 23, 2020, before costs and taxes, marked weekly. Each purchase gets the same starting stake, bought at the close of the first trading day after the report and sold 12 months later or the day after a reported sale of that stock; uninvested money earns the Treasury bill rate. “Same days invested” holds the S&P 500 only on the days the copy held shares, Treasury bills otherwise.
Return a year, copying
+25.6%
S&P 500, same days invested
+15.4% (held throughout +22.0%)
Time in shares
69%
Sharpe ratio (S&P 500)
0.64 (1.03)
Biggest drop (S&P 500)
−86% (−25%)
Market sensitivity (beta)
1.54
Purchases copied
6

Trade by trade

Nebreda Julian: trades against the S&P 500 afterwards
MeasuredTrades countedAverage vs S&P 500MedianWent the right wayYearst-statisticp-valueEvidence
Purchases, 3 months after the report 6 −3.0% −11.3% 17% 4 0.06 0.96 No reliable evidence
Purchases, 6 months after the report 6 +15.7% +16.3% 100% 4 4.71 0.018 Some evidence: ahead
Purchases, 12 months after the report 6 +59.0% +47.7% 83% 4 0.87 0.45 No reliable evidence
Purchases, 12 months after the trade 6 +78.2% +73.9% 83% 4 1.08 0.36 No reliable evidence
Sales, 3 months after the report 1 +18.3% +18.3% 0% 1 — — Not enough years
Sales, 12 months after the report 1 +0.3% +0.3% 0% 1 — — Not enough years
Sales, 12 months after the trade 1 −2.0% −2.0% 100% 1 — — Not enough years

“Average vs S&P 500” is the stock’s return including dividends minus the index’s over the same dates, from the close on the first trading day after the report, or from the close on the trade date. Only windows that have finished are counted. For sales, a negative figure means the stock lagged after it was sold, so selling was the right call (green). “Went the right way” is the share of purchases that beat the index, or of sales that trailed it. The t-statistic uses one average per year of reports, because one person’s trades bunch into the same stock and weeks, and needs trades in at least four different years; the p-value comes from the t distribution with that number of years (with four years, a t of 2 has p = 0.14). “Some evidence” means p under 5%, “strong evidence” p under 1% over at least six years.

Companies traded

CompanyTitle on the latest filingPurchasesSalesFirst reportLatest report
Fluence Energy, Inc. FLNC President and CEO50February 16, 2022March 17, 2025
AES Corporation AES SVP, Andes SBU President11September 4, 2019March 20, 2020

Trades and what followed

Moves are against the S&P 500; green means the trade went the insider’s way.

ReportedTradedCompanyTradeValue3 months after report12 months after report12 months after trade
March 17, 2025March 14, 2025 FLNC Purchase $49,707 −3.9%+171.9%+201.1%
February 18, 2025February 13, 2025 FLNC Purchase $149,225 −18.8%+127.8%+174.4%
March 4, 2024March 4, 2024 FLNC Purchase $98,959 +46.3%−77.2%−78.3%
August 19, 2022August 18, 2022 FLNC Purchase $203,952 −0.9%+36.3%+24.5%
February 16, 2022February 15, 2022 FLNC Purchase $104,000 −19.7%+50.1%+65.7%
March 20, 2020March 19, 2020 AES Purchase $28,500 −21.0%+45.3%+82.0%
September 4, 2019August 30, 2019 AES Sale $287,547 +18.3%+0.3%−2.0%

Open-market purchases and sales of at least $10,000 in companies we cover, from SEC Form 4 filings; sales made under a pre-set Rule 10b5-1 plan are not shown. “Not yet” means the window has not finished or the share price was under $5 at entry. These are the shares’ moves after each trade: they say nothing about why Nebreda Julian traded and do not suggest the use of non-public information. How every insider compares · the insider trading backtest.