A boundary is not an exact price
A buy limit of 103 roubles permits execution at 103 or less; it does not require spending exactly 103 per security. If an offer at 102 is available, execution may be better. The limit does not create a seller. Missing volume, a changing book and priority rules may leave the order unfilled. “Price reached the limit” is also insufficient: the observed trade may have had another size or occurred before the order was processed.
In a static educational book, 20 securities are offered at 102, 30 at 103 and 10 at 106. A buy of 60 with a limit of 103 can execute 50 securities for 5,130 roubles; the remaining 10 fail the price condition. The remainder depends on validity and order rules. A market purchase of all 60 would also use 106. The book is assumed unchanged and other constraints excluded; real execution is not guaranteed.
Partial execution is a separate status
An order and a trade do not have a mandatory one-to-one relationship. One instruction can produce several fills at different prices and times. The report should reconcile original quantity, filled quantity, cancelled remainder and active remainder. A pre-final interface value may differ from the final result. If several rows appear, first check identifiers and their link to the original order rather than assuming the broker created an extra independent purchase.
Validity, activation condition and price boundary are different parameters. Not every option exists in every app or regime. An instruction may appear on the market only after a defined event; the event does not set the later execution price. Do not infer identical processing from an identical button label. Universal cancellation rules and cutoff times are not specified here because the particular system documents must be checked.
Why the last price is not a cost calculation
Investor.gov states that the last trading price need not become the execution price of a market order.[4](#source-cm-orders) The bid–ask difference can also create a cost without a visible chart move; the SEC discusses this for exchange-traded funds.[5](#source-cm-etf) Multiplying quantity by last price is therefore only an estimate under explicit assumptions. A bond also requires [accrued interest](/guides/accrued-interest/), and commissions and other costs remain.
A checking card should answer four questions: quantity, acceptable prices, validity and what the report confirms. Record separately what happens to the unfilled remainder. This helps read a system message but does not predict the market or replace obligation analysis. [Settlement guidance](/guides/exchange-and-settlement/) covers infrastructure, and [chart literacy](/guides/chart-literacy/) covers last-price errors.
Check the result, not the button name
“Partially filled” does not say whether the remainder stays active. Reconcile validity, cancellation conditions and system confirmation. A cancellation command is not proof that no fill already occurred; first obtain final status and report. Message order has its own timestamps, and a changed user intention does not rewrite a confirmed trade.
If the report’s average price is better than the limit, was the order violated? Not necessarily: the limit is a boundary, not an exact price. But one average cannot prove every fill met the conditions; inspect the details. Preserve original parameters and compare each result row. If the discrepancy is unclear, ask the responsible participant for an explanation rather than assuming guaranteed favourable execution.
Activation condition: stop, stop-limit and trailing
A stop condition answers when an instruction activates. In a simple stop, activation creates a market order, so the trigger does not guarantee the exit price. A stop-limit creates a limit order: it preserves a price boundary but may remain unfilled after a gap. In a trailing version, the condition level changes by an agreed rule as selected price movement develops, rather than remaining the original number. The SEC explains these mechanisms and differences in intermediary activation standards.[44](#source-cm-advanced-orders)
This is not advice on a gap, loss percentage or chart signal. Automation does not guarantee the result. Check which measure triggers the condition, where it is stored, how it behaves during a pause and what becomes active afterward. A personal conditional order is not the same as forced liquidation under margin rules; the grounds and decision-making parties differ.
How a number becomes a condition: percentage, chart and volatility
A percentage gap must use an explicit base. In an educational long position entered at 100, an 8% gap gives a conditional level of 92, not a maximum loss of 8%. FINRA warns that a stop becomes a market instruction after activation and the available price can differ substantially.[19](#source-mk-finra-stop) If a gap permits execution only at 85, model loss is 15 per unit before costs, not 8.
A chart stop may use a selected series value, such as a prior low of 95 less a gap of 1, giving 94. The low, window and gap are author assumptions. Another candle interval, adjusted series or low gives another level. Lo and co-authors stress formalising chart features for testing; the work does not confirm a universal profitable level.[22](#source-rm-technical-lo) “Support” does not create a buyer at activation.
A volatility version scales the gap by a selected measure of past movement. If the author’s average range is 3 and multiplier 2, the gap is 6 and the level from 100 is 94. For a range of 5, the same multiplier gives a gap of 10 and level 90. A money-denominated range and percentage return standard deviation have different units and cannot share a formula without conversion. All figures compare mechanics, not reader settings.
Stop-out is a margin requirement, not a personal order
Forced position reduction comes from margin rules and contract terms, not an owner’s chosen chart line. FINRA describes possible liquidation for insufficient capital, changing house requirements and responsibility for a post-sale deficit in U.S. margin accounts.[20](#source-mk-finra-margin-full) U.S. percentages are not transferred to Russian accounts, futures or OTC foreign-exchange contracts. “Stop-out” can mean different measures and procedures at different intermediaries.
In the author’s model, borrowing is 8,000, assets are worth 10,000 and capital is 2,000. A fictional contract requires capital of at least 20% of asset value. At assets of 9,000, capital is 1,000 against a model requirement of 1,800: deficit 800. This is an educational rule, not a current norm. At an immediate fall to 7,500, capital is already −500; being above the threshold earlier did not guarantee timely closure. Valuation basis, notice procedure, choice of property sold and gap consequences must be read separately. A personal stop-limit may remain unfilled while the intermediary’s risk procedure continues.