奎斯特診斷公司
US ˙ NYSE ˙ US74834L1008

SecurityDGX / Quest Diagnostics Incorporated
InstitutionTcw Group Inc
Latest Disclosed Ownership30,862 shares
Latest Disclosed Value $ 6,048,335
Tcw Group Inc reports 7.50% increase in ownership of DGX / Quest Diagnostics Incorporated

On May 14, 2026 - Tcw Group Inc filed a 13F-HR form disclosing ownership of 30,862 shares of Quest Diagnostics Incorporated (US:DGX) valued at $6,048,335 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 28,708 shares of Quest Diagnostics Incorporated. This represents a change in shares of 7.50% during the quarter. The current value of the position is $6,052,655 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-14 2026-03-31 13F QUEST DIAGNOSTICS COM 74834L100 30,862 2,154 7.50 6,048 21.42 0.0455
2026-02-17 2025-12-31 13F QUEST DIAGNOSTICS COM 74834L100 28,708 2,131 8.02 4,982 -1.66 0.0357
2025-11-14 2025-09-30 13F QUEST DIAGNOSTICS COM 74834L100 26,577 6,724 33.87 5,065 42.04 0.0424
2025-08-14 2025-06-30 13F QUEST DIAGNOSTICS COM 74834L100 19,853 4,471 29.07 3,566 37.05 0.0279
2025-05-07 2025-03-31 13F QUEST DIAGNOSTICS COM 74834L100 15,382 15,382 2,603 0.0233
2017-11-06 2017-09-30 13F QUEST DIAGNOSTICS COM 74834L100 0 -14,749 -100.00 0 -100.00
2017-08-11 2017-06-30 13F QUEST DIAGNOSTICS COM 74834L100 14,749 -228,604 -93.94 1,639 -93.14 0.0136
2017-05-11 2017-03-31 13F QUEST DIAGNOSTICS COM 74834L100 243,353 -86,776 -26.29 23,894 -21.24 0.1993
2017-02-10 2016-12-31 13F QUEST DIAGNOSTICS COM 74834L100 330,129 -12,479 -3.64 30,339 4.64 0.2284
2016-11-14 2016-09-30 13F QUEST DIAGNOSTICS COM 74834L100 342,608 -16,386 -4.56 28,995 -0.79 0.2202
2016-08-12 2016-06-30 13F/A-1 QUEST DIAGNOSTICS COM 74834L100 358,994 -18,844 -4.99 29,225 8.25 0.2208
2016-08-11 2016-06-30 13F QUEST DIAGNOSTICS COM 74834L100 358,994 29,225
2016-05-16 2016-03-31 13F QUEST DIAGNOSTICS COM 74834L100 377,838 2,028 0.54 26,997 0.98 0.1980
2016-02-16 2015-12-31 13F QUEST DIAGNOSTICS COM 74834L100 375,810 22,929 6.50 26,735 23.25 0.1920
2015-11-13 2015-09-30 13F QUEST DIAGNOSTICS COM 74834L100 352,881 -28,869 -7.56 21,691 -21.65 0.1556
2015-08-12 2015-06-30 13F QUEST DIAGNOSTICS COM 74834L100 381,750 -118,969 -23.76 27,685 -28.05 0.1783
2015-05-13 2015-03-31 13F QUEST DIAGNOSTICS COM 74834L100 500,719 -36,404 -6.78 38,480 6.83 0.1847
2015-02-13 2014-12-31 13F QUEST DIAGNOSTICS COM 74834L100 537,123 36,385 7.27 36,020 18.55 0.1507
2014-11-14 2014-09-30 13F QUEST DIAGNOSTICS COM 74834L100 500,738 28,769 6.10 30,385 9.69 0.1222
2014-08-14 2014-06-30 13F QUEST DIAGNOSTICS COM 74834L100 471,969 66,844 16.50 27,700 18.05 0.1141
2014-05-13 2014-03-31 13F QUEST DIAGNOSTICS COM 74834L100 405,125 170,775 72.87 23,464 86.99 0.0974
2014-02-18 2013-12-31 13F/A-1 QUEST DIAGNOSTICS COM 74834L100 234,350 159,350 212.47 12,548 170.78 0.0529
2014-02-14 2013-12-31 13F QUEST DIAGNOSTICS COM 74834L100 12,548 234,350
2013-11-14 2013-09-30 13F QUEST DIAGNOSTICS COM 74834L100 75,000 -2,550 -3.29 4,634 -1.45 0.0214
2013-08-14 2013-06-30 13F/A-1 QUEST DIAGNOSTICS COM 74834L100 77,550 77,550 4,702 0.0232
2013-08-14 2013-06-30 13F QUEST DIAGNOSTICS COM 74834L100 77,550 4,702
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.