Arkolith/Funds/Mason Investment Advisory Services, Inc.

Mason Investment Advisory Services, Inc.

CIK 1635007
Holdings as of Mar 31, 2026·disclosed May 14, 2026·~44-day 13F lag·13F-HR
Inactive

Mason Investment Advisory Services, Inc. holds a concentrated book of 49 stocks worth $2.2B as of Q1 2026 (disclosed May 14, 2026, a ~45-day 13F lag). This quarter they opened AMERICAN CENTY ETF TR and trimmed AMERICAN CENTY ETF TR. Their largest long position is AMERICAN CENTY ETF TR at 36% of the equity book.

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Use Arkolith to show Mason Investment Advisory Services, Inc.'s latest
holdings, largest changes, and filing provenance.
Opened
2
new positions
Added to
23
existing
Trimmed
15
reduced
Sold out
1
exited

Concentration

Top-heavy: concentrated book

Top 5 holdings
93%
Top 10 holdings
98%
Top 20 holdings
99%

Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.

Direct sector allocation

0% mapped to company sectors

ETF / fund or unclassified
100%
Energy
0%
Health Care
0%
Financials
0%

Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.

Biggest moves: latest quarter

Estimated $ traded · quarter-end prices, no cost basis

Bought
  • AMERICAN CENTY ETF TR
    New$9.6M
  • T ROWE PRICE ETF INC
    +4.3%$9.1M
  • CAPITAL GROUP GROWTH ETF
    +28%$3.2M
  • CAPITAL GROUP INTL FOCUS EQT
    +15%$3.1M
  • CAPITAL GROUP DIVIDEND VALUE
    +1.8%$608K
  • TAIWAN SEMICONDUCTOR MANUFAC
    New$203K
Trimmed / exited

Holdings: largest first

Bars show each stock's share of the portfolio. Click a row for its position history.

79 positions
#SecurityValueShares% PortLast moveHistory
1Ishares TR
MSCI USA VALUE
$660.5M4.64M
30.5%
−1.0%
Reduced · −48K sh
2American Centy ETF TR
US SML CP VALU
$313.0M2.83M
14.5%
−0.4%
Reduced · −12K sh
3Vanguard Intl Equity Index F
FTSE SMCAP ETF
$277.8M1.91M
12.8%
−1.7%
Reduced · −32K sh
4American Centy ETF TR
INTL SMCP VLU
$235.7M2.36M
10.9%
−2.3%
Reduced · −56K sh
5American Centy ETF TR
AVANTIS US SMALL
$223.4M3.59M
10.3%
−0.6%
Reduced · −22K sh
6T Rowe Price ETF Inc
GROWTH ETF
$220.8M5.62M
10.2%
+4.2%
Added · +225K sh
7Vanguard Index FDS
SM CP VAL ETF
$61.5M283.0K
2.8%
−0.8%
Reduced · −2K sh
8Capital Group Dividend Value
SHS CREATION UNI
$34.2M803.4K
1.6%
+1.8%
Added · +14K sh
9Pimco ETF TR
ENHAN SHRT MA AC
$28.0M278.2K
1.3%
−7.7%
Reduced · −23K sh
10Capital Group Intl Focus Eqt
SHS CREATION UNI
$23.9M811.7K
1.1%
+15%
Added · +104K sh
11Capital Group Growth ETF
SHS CREATION UNI
$14.7M365.1K
0.7%
+28%
Added · +81K sh
12American Centy ETF TR
AVANTIS TOTAL EQ
$9.6M204.8K
0.4%
New
New position
13Dimensional ETF Trust
US TARGETED VLU
$7.5M120.3K
0.3%
~0%
Added · +30 sh
14Vanguard Intl Equity Index F
GLB EX US ETF
$7.1M160.1K
0.3%
−0.1%
Reduced · −169 sh
15State STR SPDR S&P 500 ETF T
TR UNIT
$3.4M5.3K
0.2%
~0%
Reduced · −1 sh
16Exxon Mobil Corp
COM
$2.8M16.3K
0.1%
−0.1%
Reduced · −10 sh
17Ishares TR
EAFE VALUE ETF
$2.5M33.1K
0.1%
Held
18Schwab Strategic TR
FUNDAMENTAL INTL
$2.2M44.9K
0.1%
Held
19Chevron Corporation
COM
$2.1M10.3K
0.1%
+0.1%
Added · +11 sh
20Vanguard Index FDS
GROWTH ETF
$1.8M4.2K
0.1%
+149%
Added · +2K sh
21Dimensional ETF Trust
US CORE EQUITY 2
$1.5M38.5K
0.1%
−1.0%
Reduced · −377 sh
22Vanguard Scottsdale FDS
SHORT TERM TREAS
$1.5M25.2K
0.1%
+0.6%
Added · +152 sh
23Apple Inc
COM
$1.3M5.0K
0.1%
−1.3%
Reduced · −65 sh
24Ishares TR
CORE 80/20 AGGRE
$1.2M13.4K
0.1%
+17%
Added · +2K sh
25Wisdomtree TR
US MIDCAP FUND
$1.2M17.4K
0.1%
Held
26Vanguard World FD
ENERGY ETF
$1.2M6.7K
0.1%
+2.1%
Added · +139 sh
27State STR SPDR S&P Midcap 40
UTSER1 S&PDCRP
$1.1M1.8K
0.1%
Held
28Vanguard Index FDS
TOTAL STK MKT
$1.1M3.3K
0.0%
+0.3%
Added · +11 sh
29SPDR Series Trust
STATE STREET SPD
$994K13.0K
0.0%
Held
30Vanguard Specialized Funds
DIV APP ETF
$959K4.5K
0.0%
+0.2%
Added · +10 sh
31SPDR Series Trust
STATE STREET SPD
$941K16.6K
0.0%
+0.1%
Added · +21 sh
32Ishares TR
EAFE SML CP ETF
$927K11.8K
0.0%
Held
33SPDR Index SHS FDS
STATE STREET SPD
$885K11.9K
0.0%
Held
34Vanguard Index FDS
VALUE ETF
$825K4.2K
0.0%
+13%
Added · +499 sh
35Microsoft Corp
COM
$799K2.2K
0.0%
+1.2%
Added · +26 sh
36Vanguard Mun BD FDS
TAX EXEMPT BD
$764K15.3K
0.0%
+13%
Added · +2K sh
37Ishares TR
RUS 1000 GRW ETF
$753K1.8K
0.0%
Held
38Vanguard Index FDS
REAL ESTATE ETF
$723K8.1K
0.0%
−2.2%
Reduced · −182 sh
39Albertsons Cos Inc
COMMON STOCK
$719K42.2K
0.0%
+0.8%
Added · +352 sh
40Ishares TR
CORE S&P500 ETF
$712K1.1K
0.0%
−6.0%
Reduced · −70 sh
41Vanguard Index FDS
EXTEND MKT ETF
$669K3.3K
0.0%
+0.1%
Added · +3 sh
42Vanguard Whitehall FDS
HIGH DIV YLD
$649K4.4K
0.0%
−3.9%
Reduced · −179 sh
43Vanguard World FD
MATERIALS ETF
$632K2.8K
0.0%
−0.1%
Reduced · −2 sh
44Arista Networks Inc
COM SHS
$608K5.0K
0.0%
−14%
Reduced · −798 sh
45Vanguard Index FDS
LARGE CAP ETF
$533K1.8K
0.0%
−16%
Reduced · −343 sh
46Alphabet Inc
CAP STK CL C
$532K1.9K
0.0%
−18%
Reduced · −396 sh
47Vanguard Index FDS
S&P 500 ETF SHS
$497K831
0.0%
−2.4%
Reduced · −20 sh
48Ishares TR
CORE S&P MCP ETF
$494K7.3K
0.0%
~0%
Added · +1 sh
49Alphabet Inc
CAP STK CL A
$441K1.5K
0.0%
−23%
Reduced · −465 sh
50Ishares TR
RUS 1000 VAL ETF
$432K2.0K
0.0%
−43%
Reduced · −2K sh
Showing 50 of 79 positions

Filing history

As-of date vs the date the SEC received each filing

QuarterAs ofFiledPositionsValueForm
Q1 2026Mar 31, 2026May 14, 202679$2.2B13F-HR
Q4 2025Dec 31, 2025Feb 12, 202680$2.1B13F-HR
Q3 2025Sep 30, 2025Nov 12, 202580$2.0B13F-HR
Q2 2025Jun 30, 2025Aug 5, 202574$1.8B13F-HR
Q1 2025Mar 31, 2025May 1, 202574$1.7B13F-HR
Q4 2024Dec 31, 2024Feb 6, 202571$1.7B13F-HR
Q3 2024Sep 30, 2024Nov 12, 202473$1.7B13F-HR
Q2 2024Jun 30, 2024Aug 9, 202473$1.6B13F-HR
Q1 2024Mar 31, 2024May 13, 202467$1.4B13F-HR
Q4 2023Dec 31, 2023Feb 13, 202464$1.4B13F-HR
Q3 2023Sep 30, 2023Aug 8, 202463$1.1B13F-HR
Q2 2023Jun 30, 2023Aug 8, 202463$1.2B13F-HR
Q1 2023Mar 31, 2023Aug 8, 202459$1.1B13F-HR
Q4 2022Dec 31, 2022Aug 7, 202486$983.4M13F-HR
Q3 2022Sep 30, 2022Aug 7, 202488$871.1M13F-HR
Q2 2022Jun 30, 2022Aug 7, 202486$971.4M13F-HR
Q1 2022Mar 31, 2022Aug 7, 202495$1.2B13F-HR
Q4 2021Dec 31, 2021Aug 6, 2024100$1.2B13F-HR
Q3 2021Sep 30, 2021Aug 6, 202494$968.6M13F-HR
Q2 2021Jun 30, 2021Aug 6, 202494$988.8M13F-HR
Q1 2021Mar 31, 2021Aug 6, 202484$958.0M13F-HR
Q4 2020Dec 31, 2020Aug 5, 202481$833.2M13F-HR
Q3 2020Sep 30, 2020Aug 5, 202475$697.3M13F-HR
Q2 2020Jun 30, 2020Aug 5, 202478$673.5M13F-HR

Data source

Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. The performance line is a simulation of the disclosed long book, not an audited return.