Tudor David J

Director at NBR

CIK 0001432308 · All filings on EDGAR ↗

0Buy txns

1Sell txns

+$0Reported buys

−$295kReported sells

0Cluster events

cumulative reported $ across trade dates, 2026-08-28 → 2026-08-28

Sectors: Materials

Career transactions in this dataset

Filing date	Trade date	Ticker	Insider	Type	Shares	Price	Value	Cluster
2026-08-28	2026-08-28	NBR	Tudor David J Director	S	3,200	$92.30	−$295k	—

Known data limitations

Form 4 lag: insiders have 2 business days to file after a trade (weekends and holidays extend this), and this site re-ingests once daily — a transaction can appear here roughly three business days after it happened.

13F lag: quarterly 13F-HR holdings cover the prior quarter-end and are due 45 days after it — every institutional position shown here is at least 45 days old by construction, often more.

CUSIP→ticker gaps: 13F positions are reported by CUSIP; some holdings cannot be matched to a current ticker (delistings, corporate actions, thin metadata) and appear without one or are omitted from ticker-level views.

EDGAR timing variability: institutions file at different hours and days within their windows; amended filings (4/A, 13F-HR/A) can restate earlier periods, so historical aggregates may change between batches.

Insider Atlas is a descriptive research site, not investment advice — see the methodology for the full provenance chain.