0000917286
2025-10-31
2025-10-31
0000917286
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2025-10-31
2025-10-31
0000917286
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frdf:C000276119Member
2025-10-31
2025-10-31
0000917286
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2025-10-31
2025-10-31
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2025-10-31
2025-10-31
0000917286
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frdf:InterestRateChangesMember
2025-10-31
2025-10-31
0000917286
frdf:S000105361Member
frdf:IncomeRiskMember
2025-10-31
2025-10-31
0000917286
frdf:S000105361Member
frdf:IssuerSpecificChangesMember
2025-10-31
2025-10-31
0000917286
frdf:S000105361Member
frdf:USTreasuryObligationsMember
2025-10-31
2025-10-31
0000917286
frdf:S000105361Member
frdf:StablecoinIssuerReservesRiskMember
2025-10-31
2025-10-31
iso4217:USD
pure
N-1A
Fidelity Hereford Street Trust
2026-06-12
Investment Objective
<div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 3pt; margin-left: 0pt; text-align: left;">Fidelity<sup>®</sup> Reserves Digital Fund seeks to obtain as high a level of current income as is consistent with the preservation of capital and liquidity. </div>
Fee Table
<div class="BRDSX_fpara" style="margin-bottom: 10pt; color: #000000; font: 10.02pt Arial, Helvetica, sans-serif; margin-top: 3pt; margin-left: 0pt; text-align: left">The following table describes the fees and expenses that may be incurred when you buy, hold, and sell shares of the fund. <span style="font-weight: bold;">You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span></div>
<table cellpadding="0" class="BRDSX_fintab" style="width: 326pt; margin-left: auto; margin-right: auto; border-spacing: 0px;"><tr class="BRDSX_boxspacer"><td style="height: 6pt; width: 304.53pt; background-color: white;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 2pt; background-color: white;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 2pt; background-color: white;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 14.47pt; background-color: white;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 3pt; background-color: white;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 304.53pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; font-weight: bold; margin-top: 1pt; margin-left: 0pt; text-align: left;">Shareholder fees <br/></div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-weight: bold; margin-top: 0pt; margin-left: 0pt; text-align: left; font-size: 8pt;"><span style="font-size: 8pt;">(fees paid directly from your investment)</span></div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 14.47pt; text-align: center; vertical-align: bottom; background-color: #D2F7FA; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;">None</div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr class="BRDSX_boxspacer"><td style="height: 3pt; width: 304.53pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 14.47pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr></table>
Shareholder fees (fees paid directly from your investment)
0
<table cellpadding="0" class="BRDSX_fintab" style="margin-top: 4pt; width: 326pt; margin-left: auto; margin-right: auto; border-spacing: 0px;"><tr class="BRDSX_boxspacer"><td colspan="4" style="height: 6pt; width: 323pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td colspan="4" style="width: 323pt; padding-bottom: 2pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; font-weight: bold; margin-top: 0pt; margin-left: 0pt; text-align: left;">Annual Operating Expenses <br/> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-weight: bold; margin-top: 0pt; margin-left: 0pt; text-align: left; font-size: 8pt;"><span style="font-size: 8pt;">(expenses that you pay each year as a % of the value of your investment) </span></div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.74pt; padding-bottom: 2pt; text-align: left; vertical-align: bottom;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">Management fee</div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.74pt; padding-bottom: 2pt; text-align: center; vertical-align: bottom; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.83pt;">0.25% </span></div></td><td style="width: 3pt;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.74pt; padding-bottom: 2pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">Distribution and/or Service (12b-1) fees</div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.74pt; padding-bottom: 2pt; text-align: center; vertical-align: bottom; background-color: #D2F7FA; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.53pt;">None </span></div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.74pt; padding-bottom: 2.25pt; text-align: left; vertical-align: bottom;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">Other expenses</div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.74pt; padding-bottom: 2.25pt; text-align: center; vertical-align: bottom; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.83pt; border-bottom: 1pt solid #000000; padding-bottom: 3pt;">0.00</span><span style="padding-bottom: 3pt;">%<sup>A</sup> </span></div></td><td style="width: 3pt;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.99pt; padding-bottom: 2pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; font-weight: bold; margin-top: 0pt; margin-left: 0pt; text-align: left;">Total annual operating expenses</div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.99pt; padding-bottom: 2pt; text-align: center; vertical-align: bottom; background-color: #D2F7FA; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.83pt;">0.25% </span></div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.74pt; padding-bottom: 2.25pt; text-align: left; vertical-align: bottom;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">Fee waiver and/or expense reimbursement</div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.74pt; padding-bottom: 2.25pt; text-align: center; vertical-align: bottom; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.83pt; border-bottom: 1pt solid #000000; padding-bottom: 3pt;">0.07</span><span style="padding-bottom: 3pt;">%<sup>B</sup> </span></div></td><td style="width: 3pt;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 303pt; padding-top: 1.99pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; font-weight: bold; margin-top: 0pt; margin-left: 10.02pt; text-indent: -10.02pt; text-align: left;">Total annual operating expenses after fee waiver and/or expense reimbursement</div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 16pt; padding-top: 1.99pt; text-align: center; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;"><span style="padding-left: 3.83pt;">0.18% </span></div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr class="BRDSX_boxspacer"><td style="height: 3pt; width: 303pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 2pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 16pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr></table><table border="0" cellpadding="0" style="margin-top: 2pt; margin-left: 0pt; border-spacing: 0px;"><tr><td style="width: 10pt; text-align: left; vertical-align: top;"><div style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 6pt;"><span style="position: relative; top: -3.25pt;">A</span><br/></div></td><td style="vertical-align: top;"><div style="color: #000000; font-family: Arial, Helvetica, sans-serif; text-align: left; font-size: 8pt;"><span style="font-size: 8pt;">Based on estimated amounts for the current fiscal year.</span></div></td></tr></table><table border="0" cellpadding="0" style="margin-top: 2pt; margin-left: 0pt; border-spacing: 0px;"><tr><td style="width: 10pt; text-align: left; vertical-align: top;"><div style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 6pt;"><span style="position: relative; top: -3.25pt;">B</span><br/></div></td><td style="vertical-align: top;"><div style="color: #000000; font-family: Arial, Helvetica, sans-serif; text-align: left; font-size: 8pt;"><span style="font-size: 8pt;">Fidelity Management & Research Company LLC (FMR) has contractually agreed to reimburse the fund to the extent that total operating expenses (excluding interest, certain taxes, fees and expenses of the Independent Trustees, proxy and shareholder meeting expenses, extraordinary expenses, and acquired fund fees and expenses (including fees and expenses associated with a wholly owned subsidiary), if any, as well as non-operating expenses such as brokerage commissions and fees and expenses associated with the fund’s securities lending program, if applicable), as a percentage of its average net assets, exceed 0.18% (the Expense Cap). If at any time during the current fiscal year expenses for the fund fall below the Expense Cap, FMR reserves the right to recoup through the end of the fiscal year any expenses that were reimbursed during the current fiscal year up to, but not in excess of, the Expense Cap. This arrangement will remain in effect through August 31, 2027. FMR may not terminate this arrangement before the expiration date without the approval of the Board of Trustees and may extend it in its discretion after that date.</span></div></td></tr></table>
Annual Operating Expenses (expenses that you pay each year as a % of the value of your investment)
0.0025
0
0
0.0025
0.07
0.0018
Based on estimated amounts for the current fiscal year.
2027-08-31
<div class="BRDSX_span2" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 6.75pt; margin-left: 0pt; text-align: justify;">This <span style="font-weight: bold;">example</span> helps compare the cost of investing in the fund with the cost of investing in other funds. Let's say, hypothetically, that the annual return for shares of the fund is 5% and that the fees and the annual operating expenses for shares of the fund are exactly as described in the fee table. This example illustrates the effect of fees and expenses, but is not meant to suggest actual or expected fees and expenses or returns, all of which may vary. For every $10,000 you invested, here's how much you would pay in total expenses if you sell all of your shares at the end of each time period indicated:</div>
<table cellpadding="0" class="BRDSX_fintab" style="width: 326pt; margin-left: auto; margin-right: auto; border-spacing: 0px;"><tr class="BRDSX_boxspacer"><td style="height: 6pt; width: 261pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 24.98pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 24.98pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 12.03pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="height: 6pt; width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 261pt; padding-bottom: 2pt; text-align: left; vertical-align: bottom; background-color: #D2F7FA;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">1 year</div></td><td style="width: 24.98pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 24.98pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td><td style="width: 12.03pt; padding-bottom: 2pt; text-align: center; vertical-align: bottom; background-color: #D2F7FA; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;">$18 </div></td><td style="width: 3pt; background-color: #D2F7FA;"><div style="font-size: 1pt;"> </div></td></tr><tr><td style="width: 261pt; padding-top: 1.74pt; text-align: left; vertical-align: bottom;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; margin-left: 0pt; text-align: left;">3 years</div></td><td style="width: 24.98pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 24.98pt;"><div style="font-size: 1pt;"> </div></td><td style="width: 12.03pt; padding-top: 1.74pt; text-align: center; vertical-align: bottom; white-space: nowrap;"><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 9pt; margin-top: 0pt; text-align: center;">$72</div></td><td style="width: 3pt;"><div style="font-size: 1pt;"> </div></td></tr><tr class="BRDSX_boxspacer"><td style="height: 3pt; width: 261pt;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 24.98pt;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 24.98pt;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 12.03pt;"><div style="font-size: 1pt;"> </div></td><td style="height: 3pt; width: 3pt;"><div style="font-size: 1pt;"> </div></td></tr></table>
18
72
Principal Investment Strategies
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 3pt; margin-left: 0pt; text-align: left;">• Investing
only in U.S. Treasury bills, notes and bonds with a remaining maturity of, or issued with
a maturity of, 93 days or less, cash, overnight repurchase agreements fully collateralized
by U.S. Treasury bills, notes and bonds, and other registered government money market funds
<span style="-keep: true">that are compliant with the Guiding and Establishing National Innovation for U.S. Stablecoins
Act (“GENIUS Act”).</span></div><div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">• Investing
only in eligible reserve assets that payment stablecoin issuers are permitted to maintain
under the <span style="-keep: true">GENIUS Act</span> and any regulations adopted thereunder.</div><div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">• Investing
in compliance with industry-standard regulatory requirements for money market funds <span style="-keep: true">as
well as any applicable GENIUS Act requirements</span> for the quality, maturity, liquidity,
and diversification of investments. <br/><br/></div>
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 8pt; margin-left: 0pt; text-align: left;">• <span style="font-style: italic;">Interest Rate Changes.</span> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">Interest rate increases can cause the price of a money market security to decrease. </div>
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 5pt; margin-left: 0pt; text-align: left;">• <span style="font-style: italic;">Income Risk.</span> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">A low or negative interest rate environment can adversely affect the fund’s yield. </div>
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 5pt; margin-left: 0pt; text-align: left;">• <span style="font-style: italic;">Issuer-Specific Changes.</span> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">A decline in the credit quality of an issuer can cause the price of a money market security to decrease. </div>
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 5pt; margin-left: 0pt; text-align: left;">• <span style="font-style: italic;">U.S. Treasury Obligations.</span> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">U.S. Treasury obligations are high-quality securities issued or guaranteed by the U.S. Treasury providing minimal risk of loss of principal if held to maturity. Fluctuations in interest rates may cause the market value of such securities to vary. </div>
<div class="BRDSX_bl" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10pt; margin-top: 5pt; margin-left: 0pt; text-align: left;">• <span style="font-style: italic;">Stablecoin Issuer Reserves Risk.</span> </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6pt; margin-left: 0pt; text-align: left;">Fund shares are expected to be held primarily by one or more stablecoin issuers as all or a portion of the </div><div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 6.75pt; margin-left: 0pt; text-align: left;">reserve assets that back the stablecoins issued to their customers. Fund assets are therefore expected to fluctuate depending on the creation of additional stablecoins or the redemption of outstanding stablecoins. Stablecoins may face periods of uncertainty or volatility that could result in rapid or unexpected redemption requests. Large redemption requests could negatively affect the fund’s liquidity, net asset value or portfolio management. Because the fund intends to invest only in certain eligible reserve assets that payment stablecoin issuers are permitted to maintain under the GENIUS Act, the fund’s yield may be lower than other money market funds that are permitted to invest in a wider universe of investments.</div>
You could lose money by investing in the fund.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance
<div class="BRDSX_fpara" style="color: #000000; font-family: Arial, Helvetica, sans-serif; font-size: 10.02pt; margin-top: 3pt; margin-left: 0pt; text-align: left;">Performance history will be available for the fund after the fund has been in operation for one calendar year. </div>
485BPOS
0000917286
false
2025-10-31