Is CSTL or SERA the better stock?

"Better" depends on your goal, and these two are not alike. CSTL is the larger company by market cap ($1.04B vs $84M). CSTL has been more active on our scanner (32 vs 0 alerts in 30 days). SERA has the smaller float (26.3M vs 28.6M), which tends to mean sharper, more volatile moves. Those are the measured differences, not a recommendation, and nothing here is investment advice.

What is the difference between CSTL and SERA?

The differences that matter: CSTL is roughly 12x the size of the other by market cap ($1.04B vs $84M); they trade at very different share prices ($34.20 vs $2.11); CSTL sits at 62% of its 52-week range against 23% for SERA; our scanner flagged CSTL 32 times in the last 30 days against 0 for SERA. Everything above is measured from the latest completed session and SEC filings.

Which of CSTL and SERA is more active right now?

Right now CSTL is at about 1.3x its normal volume and SERA is at about 0.4x, so CSTL is the one drawing unusual attention today. Relative volume (RVOL) compares a stock's volume to its own recent average, so it reads the same way for a megacap and a microcap and is the quickest way to tell which of two similar names is actually in play.

Is this comparison data live?

Prices and % changes are anchored to the latest completed session and split-adjusted, so a reverse split never shows as a fake move. Float is estimated from SEC filings and refreshed as new filings publish.

Compare

CSTL vs SERA

TheDesperateTrader.com· Side-by-side stock comparison

$CSTL vs $SERA head to head: price, market cap, valuation, dividend, free float, relative volume and how actively each trades. The bigger value in the size rows is bolded. Tap either ticker for its live chart, full ownership breakdown and real-time alerts.

$CSTLCastle Biosciences, Inc. Common Stock

$SERASera Prognostics, Inc. Class A Common Stock

$34.20

Price

$2.11

+0.0%

Day change

-1.4%

$1.04B

Market cap

$84M

—

P/E ratio

—

Dividend yield

—

28.6M

Free float

26.3M

97.04%

Institutional

47.58%

431K

Avg volume

35K

1.3x

Rel. volume

0.4x

62% of 52w

52-week range

23% of 52w

Scanner alerts 30d

SERVICES-MEDICAL LABORATORIES

Sector

SERVICES-MEDICAL LABORATORIES

CSTL vs SERA: the quick read

·CSTL is the larger company by market cap ($1.04B vs $84M).
·CSTL has been more active on our scanner (32 vs 0 alerts in 30 days).
·SERA has the smaller float (26.3M vs 28.6M), which tends to mean sharper, more volatile moves.
·Both are services-medical laboratories names, so this is a like-for-like comparison and sector news tends to move them together.
·They trade in different worlds by share price: SERA is a low-priced stock where a few cents is a real percentage move, while the other is priced for steadier increments.
·Only one of them shows up on our scanner: CSTL triggered 32 unusual-volume alerts in the last 30 days and the other triggered none.
·They are not really peers by size: CSTL is more than 12x the market cap of SERA, so the same dollar of news moves SERA far harder.

Objective differences only. Not investment advice.

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Frequently asked questions

Everything you need to know comparing CSTL and SERA on TheDesperateTrader.

Is CSTL or SERA the better stock?: "Better" depends on your goal, and these two are not alike. CSTL is the larger company by market cap ($1.04B vs $84M). CSTL has been more active on our scanner (32 vs 0 alerts in 30 days). SERA has the smaller float (26.3M vs 28.6M), which tends to mean sharper, more volatile moves. Those are the measured differences, not a recommendation, and nothing here is investment advice.
What is the difference between CSTL and SERA?: The differences that matter: CSTL is roughly 12x the size of the other by market cap ($1.04B vs $84M); they trade at very different share prices ($34.20 vs $2.11); CSTL sits at 62% of its 52-week range against 23% for SERA; our scanner flagged CSTL 32 times in the last 30 days against 0 for SERA. Everything above is measured from the latest completed session and SEC filings.
Which of CSTL and SERA is more active right now?: Right now CSTL is at about 1.3x its normal volume and SERA is at about 0.4x, so CSTL is the one drawing unusual attention today. Relative volume (RVOL) compares a stock's volume to its own recent average, so it reads the same way for a megacap and a microcap and is the quickest way to tell which of two similar names is actually in play.
Is this comparison data live?: Prices and % changes are anchored to the latest completed session and split-adjusted, so a reverse split never shows as a fake move. Float is estimated from SEC filings and refreshed as new filings publish.

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