After a company files a priced prospectus, do its shares trail comparable companies afterwards?
Study 45 · No reading (stopped by its own checks) · recorded 10 October 2026 · answer: Not settled · full paper with figures
The question
A priced prospectus is filed when a company or its holders sell securities at a set price. We compare the company's shares with five companies of the same industry and similar trading size over the month and year after, and ask whether any shortfall is brief pressure from new supply or a lasting lag after a rise before the sale.
Rules fixed before the result
Fixed in advance: before any return after a sale was computed, the study would check that it had at least 400 sales by at least 150 companies, at least 60 in each of three periods, and a comparison able to detect a shortfall of 3 percentage points over the month and 10 over the year, and stop with no answer if any check failed. No minimum or bar was changed, and the check was not run again.
Data and method
A sale is a company's first priced prospectus in 90 days, filed from 2014 to 2022 more than 180 days after its shares entered our records, taken from the regulator's public filing indexes. Each was matched once with five comparable companies of the same industry and similar trading size that filed no such prospectus within a year of it. The filings do not say whether new shares, debt or holders' shares were sold.
The answer
Not measured: the study stopped at its check of statistical power, before computing how any company's shares did after a sale. The plan required the comparison to be able to detect a shortfall of 3 percentage points over the month after and of 10 over the year after; the year's comparison could not reach that precision, so by its own rule the study stopped there. The question is answered neither yes nor no. The registration expected a lasting shortfall over the year, with low confidence, and gave a stop of any kind -- too little power, too few cases or unreadable data -- a chance of 0.15.
What it changes
No plan changed. Whether these sales become a family of events for further study stays undecided; by the plan's rule for a stop, the next step in this line of work is to find out why it could not be measured, before any new question in it.
What remains uncertain
Nothing after a sale was measured, so neither a shortfall nor its absence is shown. The year's precision depends on how widely the kept sales' returns over the year before each sale varied against those of comparable companies, and on how many sales were kept and how they cluster by company; the record does not say which put the year past its bound. The sales were counted before the plan was fixed, though no later return had been seen.