Generation Bio Co (GBIO) Earnings

0.52 ↓0.04 (-7.72%)

As of December 31, 1969, 7:00pm EST.

Last earnings report date: 0000-00-00Next earnings report date: N/A

Should You Buy GBIO Before Earnings?

Based on the last three years of earnings reports, buying GBIO stock within four weeks before its earnings date yielded an average return of -3.53%.

The best time to buy before earnings was 7 days before, which yielded an average return of 0.07% by the earnings date. The worst time was 21 days before, which yielded an average return of -7.34%.

Report dates analyzed: Aug 9 2022 - Jun 6 2025*

Disclaimer: Past performances is not a guarantee of future results.

Should You Buy GBIO After Earnings?

Based on the last three years of earnings reports, on average, GBIO has gone down -1.70% shortly after its earnings date. The stock bottoms around 28 days after earnings, where it is on average -4.41% lower than its closing price on the day of earnings.

Since GBIO has typically gone down after earnings, it might be a good time to buy the dip if you believe in the stock long-term.

Report dates analyzed: Aug 9 2022 - Jun 6 2025*

Disclaimer: Past performances is not a guarantee of future results.

Average Gains

The average return if you bought Generation Bio Co before its earnings report and sold at close on its earnings day.

Period	28 Day Before	21 Days Before	14 Days Before	7 Days Before	1 Day Before	Day Of
Past 4 Earnings	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
Past 8 Earnings	-8.64%	-11.87%	-7.67%	-0.92%	-0.20%	-0.05%
Past 12 Earnings	-4.60%	-7.34%	-4.69%	0.07%	-1.11%	-1.30%

GBIO Earnings History

Report Date	28 Day Before	21 Days Before	14 Days Before	7 Days Before	1 Day Before	Day Of	1 Day After	7 Days After	14 Days After	21 Days After	28 Days After
2025-08-06	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2025-06-06	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2025-03-04	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2024-11-07	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2024-07-31	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2024-05-08	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2024-02-21	1.80 15.00%	1.88 10.11%	1.87 10.70%	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
2023-11-01	3.19 -69.43%	3.25 -70.00%	2.41 -59.54%	0.94 3.96%	0.94 3.92%	0.98 4.29%	1.00 2.55%	1.17 19.99%	1.18 21.01%	1.15 17.94%	1.16 18.96%
2023-08-02	5.25 -14.67%	6.90 -35.07%	5.12 -12.50%	5.05 -11.29%	4.74 -5.49%	4.48 -4.68%	4.49 0.22%	4.30 -4.02%	4.53 1.12%	5.02 12.05%	5.03 12.28%
2023-05-03	3.97 13.10%	4.35 3.22%	4.51 -0.44%	4.59 -2.18%	4.59 -2.18%	4.49 -3.02%	4.64 3.34%	4.94 10.02%	4.19 -6.68%	4.27 -4.90%	3.50 -22.05%
2023-02-22	5.62 -21.71%	6.17 -28.69%	5.96 -26.17%	5.57 -21.01%	4.43 -0.68%	4.40 -0.23%	4.45 1.14%	4.03 -8.41%	4.08 -7.27%	3.61 -17.96%	3.88 -11.82%

Methodology

We analyzed the past three years of GBIO's earnings reports to calculate the average change in price of the stock before and after earnings.

Before Earnings

For calculating the average gains if you bought prior to earnings, we looked at the closing price of 5 different dates and compared them to the closing price of GBIO on the day of the earnings report to calculate the return. The dates analyzed are:

28 days prior (4 weeks)
21 days prior (3 weeks)
14 days prior (2 weeks)
7 days prior (1 week)
1 day prior

This simulates an individual purchasing GBIO stock on one of those days and selling on the day of the earnings report.

After Earnings

For calculating the average gains if you bought GBIO stock on the day of earnings, we looked at the closing price of GBIO on the day of the earnings and then compared it to 5 dates after. The dates analyzed are:

1 day after
7 days after (1 week)
14 days after (2 weeks)
21 days after (3 weeks)
28 day after (4 weeks)

This simulates an individual purchasing GBIO stock on the day of the earnings report and then selling on one of the dates following.

Day of

To calculate the gains on the day of earnings, we compared the opening price of GBIO to the closing price on the day of earnings - regardless if the earnings call was pre- or post-market.