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QuantStreet Capital

Updated today

Client assets under management

$192,641,359

Clients

26

73% high-net worth

Advisors

2

of 2 employees

Firm type

Supported

1-3 advisors or $200M+ in AUM

Clients per advisor

13

Very Low

Average account size

$7,409,283

About

QuantStreet Capital is a small, two-advisor registered investment adviser that provides discretionary investment management, financial planning, and consulting to individuals, trusts, retirement plans, businesses, and charitable organizations, and also delivers model portfolios and consulting to other investment advisers and institutional subscribers. It offers an adviser-affiliation option for independent advisers and, to a lesser extent, provides educational speaking engagements.

The firm implements a quantitative asset-allocation approach driven by a proprietary machine-learning model combined with discretionary human oversight; it offers multiple risk-targeted SMA strategies and Target-Date Replicating Portfolios that are constructed from historical return relationships. QuantStreet may use derivatives and borrowing within separately managed accounts, constrains model parameters through human review, and does not exercise discretionary authority over third‑party model subscribers who independently decide whether and how to implement the models.

Distinctive features disclosed in the brochure include the firm’s publication of hypothetical performance and performance results for its models and replicating strategies, and an affiliation between a firm principal and a law firm whose client base may overlap with the firm’s investors (a potential conflict that the firm discloses). The firm also distributes AI-generated, opt‑in news summaries and a monthly newsletter and model explanations to clients and subscribers, and generally enters separate orders for each client account rather than routinely aggregating trades into block executions.

Client services

Financial planning Portfolio management Newsletters or periodicals Educational seminars or workshops Model portfolios

Expertise

Active portfolio management Factor investing / smart beta Tax-loss harvesting

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Fee options

Fixed

Flat fees possible for consulting and speaking engagements, negotiated case-by-case; no current clients

Percentage

0.30% to 0.80% annually (negotiable based on account size, complexity, and services)

Project-based

Hourly fees for consulting and speaking engagements, negotiated case-by-case; no current clients

Subscriptions

Model portfolio subscription fees range from $1,200 to $31,000 annually, billed quarterly in advance, negotiable based on AUM and services provided

Other

Account minimum: $300,000

Main office location

QuantStreet Capital

Rye NY, United States

Number of offices

2

Most active in

Texas

Disclosures

Exclamation point means they have disclosures of this type. Check mark means no disclosures of this type were found.

Business activities & affiliations

Advisors at this firm

user avatar

Isaac M

Series 65

Rye, NY

QuantStreet Capital

Isaac Mamaysky is a financial advisor at QuantStreet Capital with four years of industry experience and holds a Series 65 designation. He has a background in law, currently attending Pace Law School and previously attending Albany Law School, and is also a practicing attorney at Potomac Law Group, PLLC. Outside of finance, he is involved with CZ Wellness Group, Inc., a business he has been part of since 2012. QuantStreet Capital provides quantitative investment management, financial planning, and consulting services to individuals, nonprofit endowments, trusts, retirement plans, and businesses. The firm uses a systematic, algorithm-driven asset allocation process across multiple risk-targeted strategies and offers model portfolio subscriptions and outside-CIO services to other advisers and asset managers.

Active portfolio management Factor investing / smart beta Tax-loss harvesting
user avatar

Harry M

Series 63, Series 65

Rye, NY

QuantStreet Capital

Harry Mamaysky is a financial advisor at QuantStreet Capital with Series 63 and Series 65 credentials and four years of industry experience. He has been with EBH Capital Management LLC since 2021 and is affiliated with Columbia Business School. QuantStreet Capital provides quantitative investment management, financial planning, and consulting services to individuals, nonprofit endowments, trusts, retirement plans, and businesses. The firm uses a systematic, algorithm-driven asset allocation process across multiple risk-targeted strategies and offers model portfolio subscriptions and outside-CIO services to other advisers and asset managers.

Active portfolio management Factor investing / smart beta Tax-loss harvesting
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