As of the latest Form 4 filed Jun 30, 2026.
What Marathon Bancorp, Inc. Common Stock insiders — officers, directors and 10% owners — have bought and sold in their own stock, straight from their SEC Form 4 filings. Values are shares × the reported transaction price where both are disclosed.
Buys plotted up, sells down; bar height is the disclosed dollar value (shares × reported price). Our Form 4 history is only complete from mid-2026, so early months are sparse — the series fills in as more filings land. Open-market purchases and sales only.
Newest filing first — the 51 most recent filings for MBBC.
| Filed | Trade date | Insider | Transaction | Shares | Price | Value | 10b5-1 | Filing |
|---|---|---|---|---|---|---|---|---|
| 2026-06-30 | 2026-06-28 | Cornish Terry SVP and CCO | FTax | −247.00 | $15.49 | $3.83K | No | Form 4 ↗ |
| 2026-06-30 | 2026-06-28 | Knopf Michelle EVP and COO | FTax | −225.00 | $15.49 | $3.49K | No | Form 4 ↗ |
| 2026-06-30 | 2026-06-28 | Zillges Nicholas W President and CEO | FTax | −1.27K | $15.49 | $19.7K | No | Form 4 ↗ |
| 2026-06-30 | 2026-06-28 | Spatz Nora EVP and CAO | FTax | −503.00 | $15.49 | $7.79K | No | Form 4 ↗ |
| 2026-06-30 | 2026-06-28 | Selting-Buchberger Joy SVP and CFO | FTax | −522.00 | $15.49 | $8.09K | No | Form 4 ↗ |
| 2026-06-17 | 2026-06-16 | Zillges Nicholas W President and CEO | PPurchase | +970.00 | $15.00 | $14.6K | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Werth Ann M Director | AAward | +3.39K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Wimmer Timothy R Director | AAward | +3.39K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Grimm Thomas L Director | AAward | +3.39K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Zientara Amy Director | AAward | +3.39K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Cornish Terry SVP and CCO | AAward | +3.50K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Knopf Michelle EVP and COO | AAward | +5.45K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Zillges Nicholas W President and CEO | AAward | +16.9K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-16 | 2026-06-15 | Spatz Nora EVP and CAO | AAward | +6.45K | $0.00 | $0.00 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-10 | Cornish Terry SVP and CCO | PPurchase | +219.00 | $14.75 | $3.23K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-10 | Knopf Michelle EVP and COO | PPurchase | +164.00 | $14.75 | $2.42K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-10 | Zillges Nicholas W President and CEO | PPurchase | +170.00 | $14.75 | $2.51K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-10 | Spatz Nora EVP and CAO | PPurchase | +602.00 | $14.75 | $8.88K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-09 | Cornish Terry SVP and CCO | PPurchase | +693.00 | $14.50 | $10.0K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-09 | Knopf Michelle EVP and COO | PPurchase | +519.00 | $14.50 | $7.53K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-09 | Zillges Nicholas W President and CEO | PPurchase | +537.00 | $14.50 | $7.79K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-09 | Spatz Nora EVP and CAO | PPurchase | +1.90K | $14.50 | $27.6K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-08 | Cornish Terry SVP and CCO | PPurchase | +71.00 | $14.24 | $1.01K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-08 | Knopf Michelle EVP and COO | PPurchase | +54.00 | $14.24 | $769.01 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-08 | Zillges Nicholas W President and CEO | PPurchase | +55.00 | $14.24 | $783.25 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-08 | Spatz Nora EVP and CAO | PPurchase | +197.00 | $14.24 | $2.81K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-05 | Cornish Terry SVP and CCO | PPurchase | +116.00 | $14.25 | $1.65K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-05 | Knopf Michelle EVP and COO | PPurchase | +87.00 | $14.25 | $1.24K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-05 | Zillges Nicholas W President and CEO | PPurchase | +90.00 | $14.25 | $1.28K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-05 | Spatz Nora EVP and CAO | PPurchase | +320.00 | $14.25 | $4.56K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-04 | Cornish Terry SVP and CCO | PPurchase | +27.00 | $13.77 | $371.73 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-04 | Knopf Michelle EVP and COO | PPurchase | +20.00 | $13.77 | $275.36 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-04 | Zillges Nicholas W President and CEO | PPurchase | +21.00 | $13.77 | $289.12 | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-04 | Spatz Nora EVP and CAO | PPurchase | +74.00 | $13.77 | $1.02K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-03 | Cornish Terry SVP and CCO | PPurchase | +263.00 | $13.75 | $3.62K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-03 | Knopf Michelle EVP and COO | PPurchase | +197.00 | $13.75 | $2.71K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-03 | Zillges Nicholas W President and CEO | PPurchase | +203.00 | $13.75 | $2.79K | No | Form 4 ↗ |
| 2026-06-11 | 2026-06-03 | Spatz Nora EVP and CAO | PPurchase | +722.00 | $13.75 | $9.93K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Zientara Amy Director | MExercise | +899.00 | $6.48 | $5.83K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Zientara Amy, Director | MExercise | +3.60K | $8.13 | $29.3K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Spatz Nora EVP and CAO | MExercise | +1.20K | $8.13 | $9.76K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Zillges Nicholas W President and CEO | MExercise | +1.50K | $6.48 | $9.72K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Grimm Thomas L Director | MExercise | +300.00 | $6.48 | $1.94K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Wimmer Timothy R Director | MExercise | +899.00 | $6.48 | $5.83K | No | Form 4 ↗ |
| 2026-06-05 | 2026-06-03 | Wimmer Timothy R, Director | MExercise | +3.60K | $8.13 | $29.3K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-05 | Werth Ann M Director | MExercise | +599.00 | $6.48 | $3.88K | No | Form 4 ↗ |
| 2026-05-06 | 2026-05-05 | Werth Ann M, Director | MExercise | +899.00 | $8.13 | $7.31K | No | Form 4 ↗ |
| 2026-03-20 | 2026-03-20 | Grimm Thomas L Director | MExercise | +599.00 | $6.48 | $3.88K | No | Form 4 ↗ |
| 2026-03-20 | 2026-03-20 | Grimm Thomas L, Director | MExercise | +3.60K | $8.13 | $29.3K | No | Form 4 ↗ |
| 2026-03-18 | 2026-03-18 | Spatz Nora EVP and CAO | MExercise | +1.92K | $6.48 | $12.4K | No | Form 4 ↗ |
| 2026-03-18 | 2026-03-18 | Spatz Nora, EVP and CAO | MExercise | +2.40K | $8.13 | $19.5K | No | Form 4 ↗ |
Insiders — a company’s officers, directors and holders of more than 10% of its stock — must report any trade in that stock to the SEC on a Form 4 within two business days. Each row here is one transaction from those filings.
The transaction code tells you what happened: Purchase (P) and Sale (S) are open-market trades — the ones markets watch most; Award (A) is a granted stock or unit, Option exercise (M) converts options into shares, and Gift (G) is a transfer for no consideration. Awards, exercises and gifts are largely compensation or administrative, not a directional bet.
One caveat on sales: many are made under a Rule 10b5-1 plan scheduled months in advance, so a sale is not automatically a bearish signal. Insider activity is a noisy input — read it alongside the filings, not on its own.
See also MBBC’s full analysis or the market-wide insider trading feed. The tabs above jump to MBBC’s other SEC data.
Source: SEC Form 4 filings for MBBC, parsed from EDGAR. Transaction prices are as reported in the filing — SEC public-domain data, not market quotes. Values are shares × reported price where both are disclosed; grants and gifts often carry no price. A delayed record of what insiders reported, not a live position or a recommendation.
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