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Mark Massey

AltaRock Partners

Mark Massey Transdigm Group Incorporated stake

total: 19

AltaRock Partners TDG trades

Total transactions:
40
New positions:
1
Added:
18
Reduced:
21
Held since:
2014 Q4
Held for:
46 quarters
Latest activity:
2026 Q1
According to 2026 Q1 report, Mark Massey holds 909,168 Transdigm Group Incorporated (TDG) shares with a market value of roughly $1.05B accounting for 25.54% of the overall portfolio. To date, the estimated cost basis is nearly $365.57 for "buy" trades and estimated average "sell" price is $683.88. AltaRock Partners first purchased TDG in 2014 Q4, initially acquiring 155,084 shares. Since the initial investment in Transdigm Group Incorporated (TDG), AltaRock Partners has made 39 more transactions.

How many TDG shares does Mark Massey currently hold?

According to 2026 Q1 report, Mark Massey holds 909,168 shares of Transdigm Group Incorporated (TDG), valued at around $1.05B.

When did Mark Massey buy Transdigm Group Incorporated (TDG)?

Mark Massey first invested in Transdigm Group Incorporated (TDG) in 2014 Q4 at the reported quarter-end price of $196.35 per share.

What's the cost basis of AltaRock Partners's TDG stake?

The estimated cost basis for Transdigm Group Incorporated (TDG) stake is around $365.57 per share. This represents their average reported price* across all buy transactions

Estimated cost basis*

Weighted AVG buy price:
$365.56
Weighted AVG sell price:
$683.88

Mark Massey's historical trades in Transdigm Group Incorporated

40 results
Period % of
portfolio
Shares
held after*
Reported
price*
Value* % (shares)
of activity
% change
to portfolio
2026 Q1
25.54%
909,168
$1,158.96
$1,053,689,345
-6.21% (-60,232)
-1.37%
2025 Q4
25.28%
969,400
$1,329.85
$1,289,156,590
-0.72% (-6,992)
-0.17%
2025 Q3
23.53%
976,392
$1,318.02
$1,286,904,184
-0.36% (-3,558)
-0.09%
2025 Q1
27.26%
979,950
$1,383.29
$1,355,555,036
-2.06% (-20,654)
-0.58%
2024 Q4
25.65%
1,000,604
$1,267.28
$1,268,045,437
-4.55% (-47,660)
-1.19%
2024 Q3
29.46%
1,048,264
$1,427.13
$1,496,009,002
-2.33% (-25,000)
-0.73%
2024 Q2
28.22%
1,073,264
$1,277.61
$1,371,212,819
-7.19% (-83,134)
-2.28%
2024 Q1
30.61%
1,156,398
$1,231.60
$1,424,219,777
-6.56% (-81,224)
-2.23%
2023 Q4
27.93%
1,237,622
$1,011.60
$1,251,978,415
-5.53% (-72,464)
-1.84%
2023 Q3
27.67%
1,310,086
$843.13
$1,104,572,809
-3.49% (-47,405)
-0.96%
2023 Q2
29.15%
$894.17
-1.85% (-25,633)
2023 Q1
27.92%
$737.05
-1.89% (-26,600)
2022 Q4
27.90%
$629.65
-6.17% (-92,655)
2022 Q3
25.81%
$524.82
+3.00% (+43,700)
2022 Q2
24.16%
$536.67
+2.63% (+37,400)
2022 Q1
23.61%
$651.54
+5.20% (+70,225)
2021 Q4
22.66%
$636.28
+1.88% (+24,872)
2021 Q3
22.34%
$624.57
+5.57% (+70,000)
2021 Q2
22.51%
$647.29
+31.87% (+303,619)
2021 Q1
21.29%
$587.92
-7.11% (-72,962)
2020 Q4
26.60%
$618.85
-16.28% (-199,436)
2020 Q3
27.45%
$475.12
+2.74% (+32,629)
2020 Q2
27.02%
$442.05
+18.04% (+182,265)
2020 Q1
20.54%
$320.19
+72.68% (+425,143)
2019 Q3
26.39%
$520.67
-3.47% (-21,000)
2019 Q2
25.29%
$483.80
-5.69% (-36,561)
2018 Q4
26.00%
$340.06
+20.22% (+108,054)
2018 Q1
18.77%
$306.94
-7.78% (-45,100)
2017 Q4
20.91%
$274.62
-10.36% (-67,000)
2017 Q3
24.17%
$255.65
+13.00% (+74,367)
2017 Q2
21.67%
$268.87
+6.73% (+36,094)
2017 Q1
17.50%
$220.16
-9.37% (-55,434)
2016 Q4
21.58%
$248.96
+34.69% (+152,356)
2016 Q2
21.04%
$263.69
-39.86% (-291,067)
2016 Q1
29.66%
$220.34
+5.03% (+34,972)
2015 Q4
32.29%
$228.45
+12.16% (+75,380)
2015 Q3
31.38%
$212.41
+42.95% (+186,242)
2015 Q2
31.07%
$224.67
+87.11% (+201,871)
2015 Q1
25.33%
$218.72
+49.44% (+76,666)
2014 Q4
25.18%
$196.35
new
* Shares, change to shares, sold shares, shares held after: split-adjusted.
* Reported price: this doesn't represent the actual buy or sell price. It is the split-adjusted price of the security as of the last day of the reported period.
If the security is completely sold out, we show the reported split-adjusted price prior to the actual period.
* Estimated cost basis: based on "Reported price*" (not earlier than 2013 Q2). Calculation starts from the latest "new buy" activity to the latest "close out" activity (if any).
* Value or Price: If the security is completely sold out, we show the reported value (or price) prior to the actual period.
* New buy or own: this means there is no earlier reporting (for us or in general). So we can't know if the actual purchase of the security happened at the reported period or earlier.