The 8-Day Invoice Objection Rule: Automating Turkish Commercial Law Deadlines

#legal #automation #javascript #fintech

In Turkish commercial law (TTK Madde 21/2), when a merchant receives an invoice, they have 8 days to formally object. If they don't, the invoice is deemed accepted. This creates a critical automation opportunity.

The Legal Framework

TTK Madde 21/2:
"Bir fatura alan kişi, aldığı tarihten itibaren 
sekiz gün içinde, faturanın içeriği hakkında bir 
itirazda bulunmamışsa, bu içeriği kabul etmiş sayılır."

Translation: If a person who receives an invoice does not object to its content within 8 days from the date of receipt, they are deemed to have accepted its content.

Why This Matters

Missing the 8-day window means:

You've legally accepted the invoice amount
You can't dispute pricing errors later
In court, the invoice becomes conclusive evidence against you
Tax implications are locked in

Building a Deadline Tracker

class InvoiceDeadlineTracker {
    constructor() {
        this.invoices = [];
    }

    addInvoice(invoiceId, receivedDate, amount, supplier) {
        const received = new Date(receivedDate);
        const deadline = new Date(received);
        deadline.setDate(deadline.getDate() + 8);

        // Skip weekends? Turkish law counts calendar days
        // but if day 8 falls on a holiday, it extends to next business day
        deadline = this.adjustForHolidays(deadline);

        this.invoices.push({
            id: invoiceId,
            received,
            deadline,
            amount,
            supplier,
            status: 'pending', // pending | objected | accepted
            daysRemaining: this.calcDaysRemaining(deadline)
        });
    }

    calcDaysRemaining(deadline) {
        const now = new Date();
        const diff = deadline.getTime() - now.getTime();
        return Math.ceil(diff / (1000 * 60 * 60 * 24));
    }

    adjustForHolidays(date) {
        // Turkish official holidays
        const holidays2026 = [
            '2026-01-01', // New Year
            '2026-04-23', // National Sovereignty
            '2026-05-01', // Labour Day
            '2026-05-19', // Commemoration of Atatürk
            '2026-07-15', // Democracy Day
            '2026-08-30', // Victory Day
            '2026-10-28', // Republic Day Eve
            '2026-10-29', // Republic Day
            // Ramadan and Eid dates change yearly
        ];

        const dateStr = date.toISOString().split('T')[0];
        while (holidays2026.includes(dateStr) || date.getDay() === 0) {
            date.setDate(date.getDate() + 1);
        }
        return date;
    }

    getUrgent(withinDays = 3) {
        return this.invoices
            .filter(inv => inv.status === 'pending' && inv.daysRemaining <= withinDays)
            .sort((a, b) => a.daysRemaining - b.daysRemaining);
    }

    objectToInvoice(invoiceId, objectionText) {
        const inv = this.invoices.find(i => i.id === invoiceId);
        if (!inv) throw new Error('Invoice not found');
        if (inv.daysRemaining < 0) {
            console.warn('⚠️ Objection period has expired!');
        }
        inv.status = 'objected';
        inv.objection = {
            text: objectionText,
            date: new Date(),
            // Should be sent via KEP for legal validity
            method: 'KEP recommended'
        };
        return inv;
    }
}

// Usage
const tracker = new InvoiceDeadlineTracker();
tracker.addInvoice('ABC2026000000042', '2026-09-22', 15000, 'Tedarikçi A.Ş.');

const urgent = tracker.getUrgent(3);
// [{ id: 'ABC2026000000042', daysRemaining: 6, ... }]

Notification Architecture

         Invoice Received
              │
              ▼
    ┌─────────────────┐
    │ Parse e-Fatura   │
    │ XML (UBL-TR)     │
    └────────┬────────┘
             │
    ┌────────▼────────┐
    │ Calculate 8-day  │
    │ deadline         │
    └────────┬────────┘
             │
    ┌────────▼────────┐     Day 1-5: Low priority
    │ Schedule alerts  │────▶ Day 6: ⚠️ Warning
    │                  │────▶ Day 7: 🔴 Urgent  
    │                  │────▶ Day 8: 🚨 Last day
    └────────┬────────┘
             │
    ┌────────▼────────┐
    │ If objecting:    │
    │ Send via KEP     │──▶ Creates legal evidence
    │ (not email!)     │
    └──────────────────┘

Integration with e-Fatura

Combine this with our e-Fatura XML Viewer to automatically parse incoming invoices and start the 8-day countdown.

Key Takeaway

The 8-day rule is one of the most commonly missed deadlines in Turkish commercial law. Automating it isn't just convenient — it's essential risk management.

All our open-source tools: github.com/eimza-kep

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